Q532
                                                        A83
                                                        6
                                                        AK1032
                      74                                                            KJ1086
                      KQJ10762                                               54
                      A43                                                         10
                      6                                                              QJ987 

                                                        A9
                                                        9
                                                        KQJ98752
                                                        54

Contract 5 Diamonds, opening lead the King of Hearts:

It looks like bidding 5D has been a good decision, as 3N hasn't got a chance on a heart lead.  If you don't bid up in diamonds for example, West will surely bid hearts, thus ensuring a heart lead.  Anyway, you win in dummy and lead a diamond to the King, losing to the Ace. West plays the Jack of hearts (therefore promising the Q) and you ruff.  Well, what have we got?  It looks like we have 7 diamonds, one heart, 2 clubs and one spade = 11 tricks.  What are the chances of a 12th?  The heart lead has taken away an important entry to dummy, so setting up the club suit (with QJx with East) is out of the question,  You could play West for QJx(x) of clubs and make an extra club by finessing the club 10 if West plays low. You could try and sneak a spade through by leading the 9 towards the Queen - but that is very unlikely to succeed.  The only hope appears to be from sort of squeeze, executed when you run your long diamonds.  You could attempt to squeeze either East or West.  To squeeze West you would need him to hold the spade K and probably QJ of clubs (when to could also win  by leading a club towards dummy).  What are the chances of that?  You know that West has at least the KQJ of hearts and Ace of diamonds.  With QJ of clubs and spade King too he might be tempted to double - so maybe East is the likely candidate?  How can this work?  If you imagine East to hold QJ of clubs and exclusive control (KJ10) in spades then he will be under extreme pressure when diamonds are run.  Taking this line you will draw trumps, play a club to the Ace and then play the Queen of Spades.  This will be covered by the King (your only chance as a defender is not actually do that and hope Declarer does not let it run!) and won by your Ace.  Now, see what happens when you run all the Diamonds.  This will be the final three-card ending-

                                                         -
                                                         -
                                                         -
                                                        K103
                                                                                  J
                      immaterial                                              -
                                                                                   -
                                                                                  QJ

                                                        9
                                                        -
                                                        2
                                                        5

So when you play your last diamond East will be subjected to an automatic squeeze.  He has to keep the QJ of clubs and therefore throw the Jack of spades - hoping Partner has the 9.  Your 9 therefore wins, making 12 tricks in all.  If you played this way then 'bridgemates' would tell you that you have just scored 100% of the available match points.    One further thing - would you like a game?

Clive Keep, April 2010