On first inspection, it might seem that you need the diamonds to break 3-3 for this contract to succeed – that is not the case. Win the trump in dummy, cash the ace of hearts and ruff a heart. Enter dummy with a trump and ruff another heart and now lead a diamond to the king to ruff yet another heart. Now enter dummy yet again, this time with a club, draw the last trump throwing the low diamond from hand and claim. This clever strategy goes by the name of a dummy reversal and demands merely that trumps break 3-2. If they do not, you will find out at the fourth trick and. With the last trump still in dummy, you would play three rounds of diamonds, hoping either that the suit breaks 3-3 or that the defender with long diamonds also has the two outstanding trumps. In the latter case, you would be able to ruff the fourth round of diamonds in dummy.