A dangerous finesse.
Bridge Column for October 29, 2000, By HARVEY BERNSTEIN
Neither side vulnerable.  West deals.
                              NORTH
                              S: K 2          
                              H: A 4 3 2     
                              D: Q J 7 6     
                              C: K 4 2   
            WEST                             EAST
            S: 9 7 4 3                       S: J 10 5   
            H: 9 7                           H: K 8 6      
            D: A K                           D: 10 8 5 2          
            C: J 8 7 5 3                     C: Q 9 6       
                              SOUTH                         
                              S: A Q 8 6
                              H: Q J 10 5   
                              D: 9 4 3     
                              C: A 10     
          The Bidding://
                   WEST   NORTH     EAST   SOUTH                  
                   Pass     1D      Pass     1H 
                   Pass     2H      Pass     4H 
                   Pass    Pass     Pass    
     We learn early in our bridge training that we can win
additional tricks by way of a "finesse".  Look at the heart suit
in today's hand.  In isolation, the location of the king of
hearts determine's how many heart tricks declarer can win in that
suit.  
     If the king is in the West hand, it can be trapped when
South leads the queen.  If West covers, South calls for the ace
from dummy.  If West fails to cover, South lets the queen ride.
     But you can't make that decision without being concerned
with how the play affects the entire hand.  Here, North-South
arrived at a very normal four heart contract.  West led the ace
of diamonds, which held the first trick.  The king of diamonds
came next, also holding the trick.  West got off lead with the
three of clubs which came around to the queen and ace.
     Declarer had lost two tricks.  How should he play the trump
suit?  First, why did West play as he did?  When asked, East
indicated that under normal conditions, the partnership had
agreed to lead the king from holdings that included the ace-king
of a non-trump suit.  But West had led the ace and then the king. 
He must be showing partner that he has only those two diamonds
and he is set to trump a diamond if East can get on lead while
West still has a trump.
     If declarer takes the heart finesse and loses, East will
lead a diamond and West will score a trick with his last little
heart, defeating the contract.  Don't take this finesse!  Lead
the queen of hearts (just in case West wants to cover with the
king), but when West plays a low heart, go up with the ace and
play a second heart back to the jack.  East will win and revert
to diamonds, but the only holding that beats you is when West
started with three hearts, which is not the case here.
     All finesses are not alike.  You have to evaluate your play
in the context of the entire hand and the information that you
have up to that point.  Trust me, your partner will appreciate
the care that you take in planning the play of the hand.
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