At teams, the auction and opening lead, the ♠Q, were the same at both tables.
At the first table, declarer won with the ♠A, throwing a club from hand, and then cashed the ♥A. The 4-0 break meant that the contract could no longer be made – the defenders would make three trump tricks and the ♦A.
The contract was made at the other table. Put yourself in the successful declarer’s seat. Can you find your way to 10 tricks?
At the other table, declarer judged that from the bidding that West was likely to be short in trumps; he decided that West was unlikely to bid 3♠ with a doubleton or tripleton heart at the vulnerability. This suggested to declarer that he might have a couple of trump losers. If that were the case, he could afford only one loser in the minor suits.
So, after ruffing the opening lead, declarer led a low diamond. West suspected that the diamonds were more-or-less as they actually were, so he rose with the ace and played a second spade. Declarer won with the ace in dummy and threw a club from hand. After ruffing a spade in hand, declarer continued to follow his plan: he played the ♦K and ♦Q, throwing two clubs from dummy. After cashing the ♣A and ruffing a club in dummy, declarer called for dummy’s remaining spade.
East saw that discarding the ♣Q would be hopeless: declarer would ruff in hand and pass the jack of trumps. East therefore ruffed in with the ♥K of trumps as declarer threw the ♣J from hand. East exited with the ♣Q, his remaining non-trump card. Declarer threw a diamond from hand and ruffed low in dummy. Declarer now paused to consider what to do next. Clearly, West had started with either a 6=1=3=3 or a 6=0=4=3 distribution. Declarer saw that cashing the ace of trumps would lose whenever East started with four trumps. On the other hand, a low trump next would lose only to a singleton trump honor with West – which was improbable, as then East would not have started with the values for a cue-bid raise of his partner’s overcall.
Accordingly, declarer led a low trump next, which limited East to just one more trump trick. Declarer had made his contract, losing only a diamond and two trumps. The full deal: