West starts out by leading the four of clubs. East wins the ace and returns a club to the king. The third club is won by the queen in the North hand, South discarding a small diamond. Declarer's problem is to play the trump suit for only one loser.
The proper play for this holding is small to the ace and then small back to the queen. The rationale is that trumps will more than likely break three-one. If by luck they divide two- two, it doesn't matter how declarer plays. Four-zero is also very difficult, but much less likely.
Let's concentrate on three-one. Fifty per cent of the time the singleton will be the jack or the king. If that is not the case, then the king-jack-small will be in the West hand fifty per cent of the remaining times, which works. Unfortunately, this hand falls into the other category. The result is an unlucky down one.
What is interesting here is what the result will be if the opening lead is the jack of diamonds?
The first thing declarer should do is win the diamond lead in the North hand and cash the ace and king of spades for an immediate club pitch. Both defenders follow so declarer leads a small spade. East plays the queen and declarer ruffs low. Now a diamond to the dummy and the jack of spades is led.
If East discards, declarer will be able to pitch his last club. If East ruffs low, declarer can over ruff and cash the ace of hearts. When both defenders follow to this trick, declarer ruffs a small diamond in dummy, over ruffed by East, who cashes the ace of clubs for the last defensive trick. The contract is made with an over trick. And this is all based on the opening lead.
So, this really wasn't a declarer play problem. All along it was an opening lead problem. The only real choices for opening lead are the jack of diamonds or the four of clubs. How does one go about deciding which is right? Look at the West hand by itself. Is there any reason to think that the jack of diamonds will get the defense pointed in the right direction? And yet, partner needs very little in the club suit to help establish defensive tricks. The opening lead is the most important play a defender can make. Try to make a lead that really counts.