North’s response of two no-trump was a Jacoby-style forcing raise in hearts. South ignored East’s intervention and asked for aces, then, once his partner admitted to three key-cards, he made a grand slam try. After North showed the diamond king, South knew what to do.

West led the spade nine, suggesting an original holding of a singleton or doubleton in the suit, given dummy’s spade eight. When trumps broke 4-0, declarer knew East had started with eight spades and five in the minors. Thus, West had to have at least one card in each minor.

Once East followed to both a top club and a diamond, there were only three unknown minorsuit cards in his hand. Therefore, East could not hold a five-card minor, so it was safe to cash a second top club, then a diamond. When East discarded on the second round of clubs, declarer ruffed a spade with the trump king. After cashing the club queen, declarer led the heart two toward dummy. West inserted the eight, and dummy’s 10 won the trick. Now declarer ruffed dummy’s remaining club with the queen, then led the heart three to the five and seven. The heart ace drew West’s last trump, while South threw a diamond. Declarer ended up with two ruffs in hand, four trumps in dummy, and seven side-suit top cards.

Note that if East had followed twice in each minor, it would have been safe to cash the queens of both minors. Finally, if East had discarded on the second diamond, then a diamond could have been ruffed safely in dummy.

In today’s deal, South’s threeno-trump call was an attempt to protect his spade tenace. An alternative would have been a stopper-showing three spades instead, to highlight the danger of the diamonds. After all, if North’s pointed-suit holdings had been interchanged, five clubs would have been far better than three no-trump. Also, curiously, three no-trump by North likely would have made on a low spade lead!

Against three no-trump, West led the second-highest spade eight to deny an honor in the suit. This went to the jack, king and ace. Declarer could see that even taking four club tricks would probably not be enough. The defense would establish the spade suit and come to five winners before he had nine.

So South decided his best chance was to sneak a heart trick first. If the heart king held, he could turn to clubs with the game-going trick in his pocket. Alas, East won the first heart and persevered with spades. Not just any spade, though. South was marked with the spade queen, and if he had started with acequeen-six, the “normal” current count return of the spade three would block the suit, assuming declarer played low.

So East put the spade 10 on the table. Declarer ducked that and won the third round, hoping for a 6-3 split. He then turned to the clubs, cashing the ace first in case West miraculously had the singleton king. But no — East won the second club and had a fourth spade to lead to West, who cashed out for down one.

When South felt obligated to break his partner’s transfer by jumping to three hearts, North used the excuse of being vulnerable at teams to press on to game.

When West led the diamond queen, South saw that the mirror distribution meant he would need not only to find both major-suit kings onside, but also some sort of endplay for his 10th trick.

Placing all the top diamonds with West after the lead and East’s discouraging signal, declarer decided he would need to eliminate West’s black suits, then throw that player in with the diamond nine. But this would also require cutting the defenders’ communications in clubs.

If the club honors were split, declarer would need to convince East rather than West to take his club entry first. Deciding that leading the club jack from dummy might persuade East to duck his ace, for fear of solving a guess for South, declarer innocently played a low club out of hand at trick two. When West played low, East had to take his ace and could do no better than return a diamond.

Declarer won this, then led a spade to the queen, followed by a trump to the king and ace. South cashed the trump queen, then played a spade to the ace to extract West’s last safe exit card.

Finally, when declarer led a club to his queen and West’s king, that player could cash his diamond winner. However, he then had to lead a minor and let declarer discard a spade loser from one hand or the other.

It is rarely attractive to upgrade 19-counts in first or second seat to a two-no-trump opening. When investigating a slam, starting the exploration at the three-level is rarely optimal. Also, it can be difficult to locate 5-3 fits after a two-no-trump start. So South was sensible to open one spade. He jumped directly to four spades when he found the fit, since his aces and kings suggested a suit contract.

When West led the diamond queen, South could see 10 tricks via a diamond ruff in dummy, as long as trumps broke 3-2. But what if they broke 4-1?

In that case, the way home would be for South to score his small trumps via heart ruffs, thus coming to six trump tricks to go with his four top side-suit winners. But this would require careful planning.

To start with, South carefully won the diamond lead in hand and continued with the heart ace and another heart. East overtook West’s 10 with the jack and shifted to the club 10. Declarer rose with the ace and played the spade queen and a trump to dummy’s king — discovering the 4-1 break.

Now came the diamond king followed by a heart, ruffed low in hand. A diamond ruff with dummy’s last trump was followed by dummy’s last heart. When East discarded his second club, declarer scored his remaining low trump, with the spade ace still to come, for the 10th trick.

If East had ruffed in on the fourth heart, South would have discarded a club instead of over-ruffing, with two more trump tricks guaranteed.

In today’s auction, South opted for a simple overcall, rather than a preempt. Then West decided on a simple raise, planning to re-compete with a further raise if he had the chance. He didn’t, because North exploited the vulnerability to drive to five diamonds, hoping his clubs would come in handy.

No one had anything further to say, but looking at his high-card values, West sensibly led out ace and another diamond. Declarer realized that there was a spade trick to lose, and now that dummy was reduced to two trumps, declarer could no longer take three heart ruffs.

In order to bring his game home, declarer realized that he needed to bring in dummy’s clubs. At trick three, he played a club to the ace and ruffed a club, bringing down the king from East. If clubs broke 3-3, declarer would have the entries he needed via heart ruffs both to set up and then to enjoy the clubs. But if clubs broke 4-2, he would be an entry short.

South found a neat solution via a variation on the Morton’s Fork. He played his spade king next. If East had taken it, the spade queen would have been the third entry to dummy, allowing declarer to set up clubs. East saw through South’s stratagem and held back the ace, but declarer countered by cashing the heart ace, ruffing a heart and then leading the club jack, on which he threw the spade four from hand. West won with the club queen, but that was the last trick for the defense.

West led the fourth highest of the unbid suit, clubs, against three no-trump, letting East encourage under dummy’s ace. Declarer immediately began work on the diamonds, leading low from dummy toward his honors. If East had followed with the eight, declarer surely would have succeeded. The winning line of crossing back to dummy in hearts and leading the diamond nine would have unblocked the suit and seen declarer come home.

However, East threw a wrench into the works when he inserted the 10 at his first turn. Given his failure to support his partner, South was all but certain to hold five diamonds, so the play was unlikely to cause harm.

West took South’s queen and continued clubs to the jack and king, dummy throwing a spade. Declarer continued diamonds from his hand, and when West played the four, he called for dummy’s six! He was trying to pick up West’s ace-king-eightlow. As it was, though, East scored his diamond eight, and down went the game.

You can hardly blame declarer here. He could have played the diamond nine on the grounds that he wasn’t down in top tricks if East showed out, but his chance of coming home would have been so small that his actual play was completely logical.

It is interesting to note that East can afford this play of the diamond 10 from honor-10-eight as well. It may feel as if you are sacrificing something of value, but there is almost no scenario where the play will cost you.

Mandatory falsecards may temporarily mislead partner, but the trade-off of confusing partner as opposed to declarer is one you can accept if the circumstances are right.

In today’s deal, South exploited the vulnerability with an aggressive four-spade opening. He had good spades, no defense and a singleton in the other major, making this a reasonable tactical move.

A minor-suit lead would have given the contract no chance, but West led a top heart, of course. On seeing the dummy and a discouraging card from his partner, West shifted to a diamond. Declarer took dummy’s ace and threw a diamond on the heart queen, setting up a trick in that suit.

Declarer ruffed the next diamond, crossed to the club ace and led a trump off dummy. When East followed low, declarer won his king. He needed to bring spades in for one loser, and if West had instinctively followed with the five, South would have had to play for ace-doubleton on his right by leading a low trump next, making his game.

However, West was aware of the situation and dropped the 10, creating a losing option for declarer where none had previously existed. South now had to decide whether West had jack-10 doubleton or jack-10-low. The Principle of Restricted Choice could not help because West had two equals either way. The only inference he had was that West might not have found this defense if he had three trumps. So South continued with the spade queen and lost his game.

Despite the disparity in North’s suits, he preferred to get his hand off his chest in one turn, hence his Michaels Cue-bid as opposed to a simple one-spade overcall. South jumped to four hearts, and West tabled the diamond queen.

With a club trick to lose, South needed to limit his trump losers to two. He won the diamond king in dummy and called for a low heart. If East followed with the nine, declarer intended to follow small. Since West had opened the bidding and had not led a top club, he seemed to have at most eight points in the minors and thus had to hold a top heart honor. Intended to duck the first heart would be beneficial if West held a singleton top heart honor, and it would almost never lose against other lines.

However, East had also been thinking ahead and had worked out that declarer must have the diamond ace, and that even if West had the spade king, it would be in the pocket. Since the defenders were entitled to at most one club trick, they needed three trumps — which could only be done if West had the heart ace. That would be simple if West had the doubleton ace, but what if it were singleton?

Hoping to put declarer off the right track, East inserted the heart jack. Now declarer could no longer duck in complete safety, since West might have aceking-nine. No count of the hand was available, and declarer was forced to guess. Can you blame him for putting up the queen and dooming his own contract?

This week’s theme involves giving your opponents a chance to go wrong. If a play has only upsides, it is clearly a useful weapon to add to your armory.

A normal auction from a teams game landed South in a poor but makeable contract on today’s deal. Not for the first time, though, the defense had other ideas, and they successfully led declarer down the garden path.

West led his fourth-highest spade against three no-trump, and declarer optimistically tried the 10, covered by the jack and ace. Needing four club tricks for his contract, declarer laid down the club ace, hoping to guess well on the next round.

When East followed with the deuce, declarer had to decide whether West had king-third or jack-third. He mentally flipped a coin and called for dummy’s 10, landing his game.

In the other room, East made declarer’s losing option more attractive by dropping the club nine under the ace, making dummy’s spot cards solid. Thus, declarer could now succeed against one 4-2 break as well — jack-nine doubleton with East. This extra chance was enough to tip the scales in favor of playing the club queen. East had swindled declarer out of his game bonus.

An interesting corollary to this is that if an expert East does not drop the nine, he cannot hold king-nine-low. However, jacknine-low is still a possibility because playing the nine from that holding would serve only to help declarer.