This deal was played (actually misplayed) in an online practice match by one of the country’s best teams. Hands are rotated to make South declarer. Vulnerable against not, North held:
♠ 5 3 2 ♥ K Q J 4 ♦ 7 ♣ A Q 10 8 7
His partner dealt and opened 1♦, overcalled with 1♠. North made a negative double. His partner cuebid 2♠. What does that show?
It says nothing about spades (neither tells nor asks). It shows a huge hand, likely forcing to game. Does it guarantee four hearts? Not necessarily. South should bid naturally, 3♣ for now.
Opener jumped to 4♥. Maybe he was afraid to bid only 3♥, thinking it not forcing. In any event, he showed more than a direct 4♥ bid and should have a hand just short of a strong twoopening.
North raised to 5♥. With such good trumps and a decent hand, he is worth a slam try. A 5-of-the-trump suit bid when the opponents have bid a suit is used to request partner to bid a slam with the opponents’ suit controlled.
South control-bid 5♠. This has to be first-round control of spades and also interest (in context) in a grand slam because it forces to a small slam. North, with great trumps and a source of tricks, indeed jumped to 7♥.
As dummy, you table your hand after the ♠K lead.
After winning the ♠A, declarer tested trumps. If they split 3–2, he would be in great shape. He could draw trumps in three rounds and then cash diamonds, throwing spade losers. If diamonds are 4–3, a diamond ruff in dummy provides the 13th trick (five trumps, four diamonds and four top black tricks). Even if diamonds don’t split, clubs can probably be set up.
Everyone followed to the first two trumps, so declarer drew a third round, LHO showing out. Now what?
Declarer tried the top diamonds, but the suit was 6–1! LHO had the singleton. Declarer threw dummy’s spades on the top diamonds and then turned his attention to clubs. He played the ♣K and then the ♣A. Disaster – RHO showed out! This was the Real Deal:
What was the error?
I like the auction, and I am happy with the early play, including cashing the top diamonds. But once diamonds were found to be 6–1, declarer needed to take stock. More accurately, he needed to do some counting and calculating.
LHO had overcalled only 1♠ at favorable vulnerability. With six spades (along with the known singleton and doubleton), he probably would have preemptively overcalled 2♠. Since he rates to have only five spades, that means he started with 5=2=1=5 shape.
Accordingly, after the ♣K drew all low clubs, declarer should have finessed the ♣10 on the second round. This would lose only if RHO had ♣J x and LHO had failed to preempt with his six-card spade suit. The bidding and odds heavily favored the winning play.