[Kaitlyn S]

Hi - these problems should be very easy for experienced players but an I/N player needs to think when playing to trick one. If you get these wrong, don't feel too bad as long as you understand the rationale for the answers. I'll provide the answers later but I'll put a hint as a spoiler. Try to solve the problem without the spoiler. Also, let me know if you would be interested in seeing more of these from time to time.

Assume that your opponents are playing Standard American (a natural system with 15-17 1NT openings and 5-card majors), IMPS, and nobody is vulnerable. Your agreed lead conventions against suits are: Ace from AKx, fourth best, low from three small.

You are East on all these deals. In each case, your partner led the indicated spade. Problem 1 is to make sure you understand standard defensive technique. You may have to think on problems 2 and 3.


1.

---

Partner leads the ♠2. Dummy plays the ♠3. Your play?

Spoiler

Do you know the standard play in this situation?

2.

---

Partner leads the ♠2. Dummy plays the ♠3. Your play?

Spoiler

If partner gets in, what do you want him to do What's the best way to accomplish that?

3

---

You ask what 3NT shows and North says "undiscussed."
Partner leads the ♠10. Dummy plays the ♠Q. Your play?

Spoiler

Will partner know what to do if he gets the lead?

OLD PROBLEM 3: This problem has been shown to be flawed. I am leaving it here only because the discussion doesn't make sense with the new hand. All the discussion before the big green post "HAND 3 HAS BEEN REPLACED" refers to the following hand.

3.

---

Partner leads the ♠10. Dummy plays the ♠Q. Your play?

Spoiler

Will partner know what to do if he gets the lead?

[Kaitlyn S]

Use the new Problem 3.

[bravejason]

Defensive play is not a strength for me. I'm just hoping what I think is correct isn't too far from being standard practice.

#1. South has the ace (partner wouldn't under lead an ace) and partner has the jack (the deuce is 4th best from an honor). So I play the ten (cheapest) to flush the ace and set up a spade trick.

#2. Same as #1 except partner has the ten. I play the queen.

#3. South has the Ace and Jack, so playing the king won't set up a trick. Therefore, play low to discourage spades.

[Kaitlyn S]

bravejason, on 2017-June-12, 15:39, said:

#1. South has the ace (partner wouldn't under lead an ace) and partner has the jack (the deuce is 4th best from an honor).

My fault! I should have listed the lead conventions that partner insisted on, which are (vs. suits): Ace from AKx, fourth best, low from three small.

I've added these to the OP.

[Kaitlyn S]

Answers:

1.

---

Partner leads the ♠2. Dummy plays the ♠3. Your play?
Hint: Do you know the standard play in this situation?

Answer: When there are no high cards in the dummy to matter, you play third hand high, but the lowest of touching cards.

Play the queen. Partner won't necessarily know that you have the king, but you do deny the jack. If you play the king, you will deny the queen. Playing the ten can't help and could hurt if declarer has the jack. This is standard.


2.

---

Partner leads the ♠2. Dummy plays the ♠3. Your play?
Hint: If partner gets in, what do you want him to do? What's the best way to accomplish that?

Answer: The "normal" play would be the ♠Q. However, when partner gets in, you really want partner to lead a club. Fool partner into thinking that there is no future in spades; play the king and make partner think declarer has the ♠AQ. Partner, when in with a red card, will lead a club because a spade lead looks futile. You'll cash your two club tricks and your "impossible" ♠Q to set the contract one trick. The recommended play is the ♠K, a falsecard intended to fool partner into doing the right thing.


3.

---

You ask what 3NT shows and North says "undiscussed."
Partner leads the ♠10. Dummy plays the ♠Q. Your play?
Hint: Will partner know what to do if he gets the lead?

Answer: First, let's look at the suit in isolation to see what the normal play is.

First, you have the king, dummy played the queen, and partner led the ten. Where are the other cards that matter?

Who has the ace?

Partner can't have it because we don't underlead aces in suit contracts. Declarer has the ♠A.

Who has the jack?

Partner can't have it because we lead top of two touching honors and would lead the jack from ♠J 10. Declarer has the jack.

Who has the nine?

The unsupported ♠10 is too valuable of a card to waste (see example below.)

...........Q 5 2
10 8 7............K 6 4 3
...........A J 9

If partner leads the ♠10, it goes ♠Q from dummy and whether you play the ♠K or not, declarer gets three tricks (if you don't play it, declarer simply finesses against it.)

...........Q 5 2
10 9 7............K 6 4 3
...........A J 8

Here the ♠10 is backed up by the ♠9. Covering the queen with the king will create a trick for partner's ♠9.

Partner should have the ♠9 (or a doubleton) for the lead of the ♠10. So, the above situation shows you where all the cards from the ace down to the nine should be based on partner's lead. If partner has a doubleton, there's nothing you can do. However, if partner has the ♠9, covering the ♠Q with the ♠K holds declarer to two spade tricks, while playing low lets declarer finesse the ♠J later for three tricks. In a vacuum, you should cover the ♠Q with the ♠K.

However, this is not a vacuum. Declarer can take six diamond tricks and if declarer doesn't have a trump loser, will take all the tricks (6 diamonds, 5 hearts, 2 spades.) If declarer has two trump losers, you set 6H. The critical case is when declarer has one trump loser. Partner will win an early trump trick. At this point, declarer will have a second spade winner whether you played the ♠K or not, and declarer will have the rest of the tricks when he gets the lead back. You would really like partner to lead a club to your ace. How do you do that?

Go back to trick one. You know what declarer's problem is if he has one. You know that partner will be wondering what to lead when in with his trump trick. If you let dummy's ♠Q win, you give declarer three spade tricks instead of two, but that is irrelevant because declarer has tons of diamonds to discard spades on anyway. The upside of not covering the ♠Q is that partner will think there is no future in spades. The only possible trick (other than an unlikely diamond ruff) is in clubs, and partner will lead a club to your ace. If you cover the ♠Q with the ♠K, partner will win his trump trick and may hope for you to have the ♠J rather than the ♣A. That would lead to a very bad result.

So, while playing the king is best when the spade suit is taken in isolation, playing low at trick 1 is recommended for this hand.


OLD PROBLEM 3 (note: this problem doesn't work as ahydra pointed out)
3.

---

Partner leads the ♠10. Dummy plays the ♠Q. Your play?
Hint: Will partner know what to do if he gets the lead?

Answer: First, let's look at the suit in isolation to see what the normal play is.

First, you have the king, dummy played the queen, and partner led the ten. Where are the other cards that matter?

Who has the ace?

Partner can't have it because we don't underlead aces in suit contracts. Declarer has the ♠A.

Who has the jack?

Partner can't have it because we lead top of two touching honors and would lead the jack from ♠J 10. Declarer has the jack.

Who has the nine?

The unsupported ♠10 is too valuable of a card to waste (see example below.)

...........Q 5 2
10 8 7............K 6 4 3
...........A J 9

If partner leads the ♠10, it goes ♠Q from dummy and whether you play the ♠K or not, declarer gets three tricks (if you don't play it, declarer simply finesses against it.)

...........Q 5 2
10 9 7............K 6 4 3
...........A J 8

Here the ♠10 is backed up by the ♠9. Covering the queen with the king will create a trick for partner's ♠9.

Partner should have the ♠9 (or a doubleton) for the lead of the ♠10. So, the above situation shows you where all the cards from the ace down to the nine should be based on partner's lead. If partner has a doubleton, there's nothing you can do. However, if partner has the ♠9, covering the ♠Q with the ♠K holds declarer to two spade tricks, while playing low lets declarer finesse the ♠J later for three tricks. In a vacuum, you should cover the ♠Q with the ♠K.

However, this is not a vacuum. Declarer can take six diamond tricks and if declarer doesn't have a trump loser, will take all the tricks. If declarer has two trump losers, you set 6H. The critical case is when declarer has one trump loser. Partner will win an early trump trick. At this point, declarer will have a second spade winner whether you played the ♠K or not, and declarer will have the rest of the tricks when he gets the lead back. You would really like partner to lead a club to your ace. How do you do that?

Go back to trick one. You know what declarer's problem is if he has one. You know that partner will be wondering what to lead when in with his trump trick. If you let dummy's ♠Q win, you give declarer three spade tricks instead of two, but that is irrelevant because declarer has tons of diamonds to discard spades on anyway. The upside of not covering the ♠Q is that partner will think there is no future in spades. The only possible trick (other than an unlikely diamond ruff) is in clubs, and partner will lead a club to your ace. If you cover the ♠Q with the ♠K, partner will win his trump trick and may hope for you to have the ♠J rather than the ♣A. That would lead to a very bad result.

So, while playing the king is best when the spade suit is taken in isolation, playing low at trick 1 is recommended for this hand.

[smerriman]

For #3, is it possible declarer has no trump losers but a diamond void? I think playing low would gift declarer the only way to make the contract.

[Tramticket]

smerriman, on 2017-June-13, 14:42, said:

For #3, is it possible declarer has no trump losers but a diamond void? I think playing low would gift declarer the only way to make the contract.

Another interesting set. Thanks.

Smerriman makes an interesting point - it is plausible for declarer to hold a diamond void.

Partner is unlikely to hold either the ace or king of trumps (declarer didn't use RKCB). Maybe, partner holds QXX in trumps and you want her to switch to clubs? I guess it might work.

But declarer is like likely to be short in diamonds on this bidding. If she has a singleton diamond, then her club losers may disappear (2 rounds of trumps then run the diamonds). So perhaps it is a reasonable option to play for declarer to have no entries to dummy?

[Kaitlyn S]

smerriman, on 2017-June-13, 14:42, said:

For #3, is it possible declarer has no trump losers but a diamond void? I think playing low would gift declarer the only way to make the contract.

Warning! This discussion is pretty advanced and may be beyond some I/N players.

Warning! This discussed the OLD flawed Hand 3.

If an I/N player gave this reason for playing the king, I would give him full credit, for it shows that he was thinking about the hand.

That being said, let's examine this scenario. Declarer has solid trumps and no diamonds, and yet few enough losers that he can make the hand if I let him win the SQ, but if I cover the SQ, he will go down.

If declarer has at least three clubs to the queen, he can force an entry to dummy by playing a club to the ♣K and later trumping a club. This will give him a club trick, a club ruff, and three diamond winners, and the two spade tricks given to him with the opening lead, and he can hardly have less than six hearts on this auction. (If he has five hearts, he either has ♥AKQJx where the heart ten is an entry anyway or partner has ♥Jxxx and declarer has a trump loser.)

If he doesn't have the ♣Q, partner led the ♠10 and not the ♣Q so declarer must have the ♣J. If declarer had the ♣J 10, he can force a dummy entry by finessing clubs (partner could hardly avoid leading the ♣A on this auction if he had it, knowing that losers are going on diamonds.) If partner holds clubs headed by the Q 10 and four small diamonds and no heart winners on an auction that suggests that declarer is going to draw trump and run diamonds, shouldn't partner prefer the more aggressive club lead to a passive ♠10 lead?

The reason I would give an I/N player full credit for that answer is that he might not be playing with a partner that would know that this auction called for an aggressive lead. An expert who isn't playing with a client or a weak significant other should be able to make the inference I described.

Maybe declarer has a singleton or doubleton ♣Q and can't force a ruffing entry? A singleton ♣Q would give partner ♣JT98xx, a pretty certain club lead. A doubleton ♣Q would give partner ♣JTxxx unless declarer's second card were the jack or ten. So, in order for the cover to win, declarer has to have S-AJx, H-AKQxxxxx (no jack or the ♥10 is a dummy entry), D- void C-QJ or C-Q10, giving partner specifically a singleton jack or queen of hearts. You can't give declarer four spades and seven hearts because declarer's spades are all good after you cover (partner's 9 drops under the J if he has it.)

However, if this is declarer's hand, he drops partner's singleton trump jack and the ♥10 becomes his dummy entry.

Fun hand - it appears to work as a defensive problem for experts also, although that was unintentional.

That being said, see 2 posts from this one.

[Kaitlyn S]

Tramticket, on 2017-June-13, 15:11, said:

Partner is unlikely to hold either the ace or king of trumps (declarer didn't use RKCB).

Warning: this discusses the OLD flawed hand 3! Presumably North didn't bid 4NT on the new Hand 3 because it could be taken as quantitative.

I stated that the opponents were playing Standard American. I used to say SAYC but in an early problem set, one of the experts complained about me using that term, suggesting that I say "natural system with 15-17 notrumps" instead. Of course, by Standard American, I still mean SAYC even though I was chastised for saying it. (In the Main Bridge Club, many if not most American players and many Chinese players suggest playing SAYC with an unknown partner.)

SAYC is described in this booklet.

ACBL SAYC booklet

You will note that regular Blackwood is used, not RKCB. The assumption that the opponents don't play RKCB isn't ridiculous unless they have specifically agreed to use it.

[Kaitlyn S]

My last two posts may appear to the casual reader to have the air of "How dare you question my solution? Take that!" but in reality nothing could be further from the truth. I am not an expert. When I play on BBO, I do not classify myself as an expert. There is a lot I don't know about the game and it is not at all unlikely that someone will find a flaw or even a serious gaffe in one of my analyses, and if that is true, I would appreciate it being pointed out. I say this simply because I don't want to discourage smerriman or Tramticket or anybody else from pointing out where my analysis is flawed if it indeed is. Several times in the past, players have correctly criticized my answers and I have corrected the solutions (or determined that my original problem was either bad or not appropriate for I/N players.) In short, I appreciate all the discussion, even that which is critical. Even if I am correct on problem 3, the respondents have pointed out that this problem has a possible alternative answer which is too difficult for an I/N player to determine isn't correct, and that if I wish to use this problem again for inexperienced players, I need to fix the problem so that a diamond void isn't a consideration (I think putting the HQ in dummy might solve the problem as either that's a dummy entry or partner has the HK making my analysis sound.)

[ahydra]

I am still wondering what the I stands for in I/N?

Must admit, the thought of playing the K on problem #2 never occurred to me. I would play Q and then try to give a suit-preference signal for clubs, or hope partner can work it out (e.g. "if I play to partner's SK and he has ♣AQ, he'll be stuck, so I need to play clubs"). Falsecarding here is quite clever and, I would say, the correct thing to do as you may not get a chance to give an SPS and/or partner won't recognize it and/or partner won't figure out to switch to a club.

On #3 if the layout is as described, would declarer necessarily play the Q?

Spoiler

Let me try to analyse in a bit more detail (probably a bit out-of-place for the N/B forum, I'll admit):

From the bidding and opening lead declarer has ♠AJ, and pretty much guaranteed ♥AK to six (if he has 7 I think it's cold; declarer didn't use RKC, so the most likely missing top heart - if any - is the Q rather than A or K).

a) Suppose declarer is 3604. We're assuming partner has a trump trick and all we need is for declarer not to be able to discard 4 clubs + 1 spade, which of course he can't because we can ruff the 4th round. So we don't have to worry about this case.

b) What about 4603? In that case I think we need to duck: consider declarer with AJ87, if we cover declarer picks up all the spades by cashing the jack.
b i) But actually: if partner has ♥Qxx I'm not sure ducking's enough. Declarer cashes three diamonds throwing his clubs, finesses the SJ and cashes the SA. If partner ruffs with a natural trump trick that doesn't help, so he discards and now declarer just ruffs his last spade, plays ♥AK and claims.
b ii) If partner has ♥QJx maybe that's good enough however - he ruffs the third round of spades, exits with say a club which declarer ruffs, and can ruff the 4th spade with his other high trump in front of dummy.

So is the correct play to duck just in case declarer is 4603 and partner has ♥QJx?! Might partner prefer leading the likely-safe ♥Q to the more dubious ♠10-doubleton?

c) For the situation where declarer is 3613, we MUST cover. Declarer will play AK hearts then run diamonds throwing clubs. Partner must follow to three rounds giving declarer enough time to discard all his clubs (partner may ruff in on the fourth round, but only after declarer has thrown the last club). Hence we won't score our club Ace and the setting trick must come from spades. This is the most likely case (that matters) I would say.

d) If declarer is 3622 partner is ruffing the 3rd round, declarer can't get both his clubs away, down one, no problem - provided we cover the spade just in case partner's putative trump trick doesn't exist!

e) If declarer has only AJ spades (2614) he wouldn't play Q here.

f) If declarer has 4612 we need to duck as discussed in b). Possible, but less likely as partner may prefer another lead.

So on balance I think I would cover, but it is a bit of a guess. No doubt my analysis a) is a bit double-dummy in places and b) contains errors.

ahydra

[Kaitlyn S]

You got me, ahydra! Problem 3 officially is a bad problem; it does not serve its intended purpose. Hand 3 was changed as a result of ahydra's post.

ahydra, on 2017-June-13, 18:22, said:

I am still wondering what the I stands for in I/N?

Intermediate.

While I typically think of both intermediate and novice as a lower level than some of these problems might indicate, I'm going along with the labels used in the Bridge Movies where a beginner is expected to figure out non-obvious suit combinations.

[smerriman]

Kaitlyn S, on 2017-June-13, 20:26, said:

You got me, ahydra! Problem 3 officially is a bad problem; it does not serve its intended purpose.

The fact it brought up a very interesting discussion makes it a good problem, even if it was unintended

[ahydra]

Kaitlyn S, on 2017-June-13, 20:26, said:

You got me, ahydra! Problem 3 officially is a bad problem; it does not serve its intended purpose.

I wouldn't trust my analysis in the spoiler as being accurate (I'm sure there are errors). The problem itself may not have fully achieved what you wanted it to, but it is certainly instructive: you show how the top six spades can be placed just from the opening lead, and you show how there is an argument for doing something unconventional in an attempt to direct partner onto the right path. Please keep making these problem series Even as an advanced player I often find something to learn from them, as in the #2 here.

ahydra

[Kaitlyn S]

HAND 3 HAS BEEN REPLACED!

The old Hand 3 in this problem set was proven to be flawed. All the discussion prior to this point concerns the old Hand 3 which is still in the original post (marked as flawed) so that the reader of this thread isn't totally confused.

I believe the new Hand 3 eliminated the flaws pointed out to me and hope that I didn't introduce any new ones!