Appearances can be deceiving. It seems that declarer will always come to nine tricks on this deal, but along the way, the defender in the East seat found a way to upset the apple cart, so to speak.
After a very normal auction with no bidding from the opposition, West led the five of hearts. Declarer ducked in dummy and when East played the queen, he ducked in hand as well. East continued with the ten of hearts which was won by the ace.
Declarer forced out the ace of clubs, East winning the third round of the suit. West discarded a small heart on this trick. East led his third heart which was won by declarer's king while a spade was discarded from the dummy.
At this point, declarer led the queen on diamonds. West played low and declarer called for the four from dummy. East, having worked out the position earlier was well prepared and contributed the three without thought.
Consider declarer's situation. If West holds the king of diamonds, as it appears, declarer can score three clubs, three diamonds, two hearts and a spade for his nine tricks and never have to concern himself with the spade position. To this end, South cashed his last club and led the jack of diamonds. West played the six, dummy the seven, and East produced the king.
A diamond return went to the ace and declarer had little choice but to play a spade towards the queen. East grabbed the king and cashed the thirteenth diamond for down one.
The question that declarer should have asked himself when the second diamond lead was not covered by West was whether West had the king or not. South knows where the ten of diamonds is. West does not. While he may very well have ducked the first diamond, almost every good player would have covered the second diamond lead. When he fails to cover, declarer should play the ace of diamonds and a third diamond. East will win and cash his last diamond, but will then have to lead from the king of spades into declarers combined holding of the ace and queen of spades.
While this appears to be a fairly advanced situation that
the average player would find difficult to handle, the point is
fairly simple; the defense is not trying to make anything easier
for the declarer. It doesn't take a "world class" defender to
decide not to take the first diamond trick. And when this kind
of play works well once or twice, that defender is going to do it
quite often. So don't take anything for granted. Count your
tricks and play with care. You could cause a defender to rue the
day he tried to fool you.
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