See if you can defend better than one of my ACBL Bulletin colleagues did. This deal was from the 2018 Spingold semifinal. West held:
♠ A 7 5 2 ♥K Q J 10 6 ♦A ♣K 7 3
With both sides vulnerable, his partner opened 2♥(!) in second seat. In this position, partner should have a good hand, so slam is definitely in the picture. Right-hand opponent overcalled 2♠ and our (anti)hero cuebid 3♠. LHO bid 4♦. When a passed hand comes in with a new suit at a high level, it should promise support (spades); it can’t be only diamonds or he would have preempted in diamonds initially. Opener bid 4♥, RHO bid 4♠, and my colleague jumped to 6♥. This was passed around to the overcaller, who now tried 6♠, doubled and passed out. What would you lead?
Expecting declarer to be able to set up diamonds, a low club was selected. Dummy played low and partner won the ♣A and returned a low club to the 9 and king. Now what?
With partner likely to have the ♥A, I would think West should be trying to get a diamond ruff. He can cash the ♦A and then play a heart to get a ruff. Which heart? Something to make sure partner wins – like the ♥Q. Partner will think declarer has the ♥K, so will win the ace and see no other choice but to issue a diamond ruff for down five (1400 in the form of two clubs, a trick in each major, the ♦A and a diamond ruff ).
This was the Real Deal:
Notice how turned on South was by North’s thoughtful 4♦ call. Personally, I think East’s hand is too good for a 2♥ preempt (three first-round controls!). Anyway, the other East–West pair reached 6♥ and made 1460. My ACBL Bulletin colleague failed to find the winning defense. After winning the ♣K at trick two, his next play was the ♥K. Now there was no entry to partner for the diamond ruff. The defense scored two clubs, a heart, a diamond and a spade for down four. Defeating the contract only 1100 lost 8 IMPs. Down 1400 (the top tricks plus a diamond ruff ) would have been a loss of only 2 IMPs; down 1700 – available by getting two diamond ruffs (with the ♦A lead) – would have been a gain of 6 IMPs. The team on the losing end of this swing lost the match by only 2 IMPs. Taking just one more trick on defense would have landed them in the Spingold final!