West leads the ♥4. Plan the play.
It’s tempting to play three rounds of hearts and pitch a diamond, but it’s too big a play. Translation: too risky. There is some chance that West has led from a doubleton heart, and if West ruffs the third heart low, you are at the mercy of the club finesse.
A better idea is not to panic: Win the ♥A and lead the ♠J. If West happens to have A–x and ducks, you have a claimer. There is no lie of cards that can defeat you at this point.
Say West wins the ♠A and leads a diamond to East who returns a club. Win the ace, draw the last trump and pitch a diamond on the third heart. If East wins the ♠A at trick two and leads a club, win the ace, draw trumps and pitch a diamond on the third heart. If the opponents cash two diamonds and then East leads a club, win the ace and discard both clubs on red-suit winners.
The inevitable fly in the ointment occurs when the player with the ♠A has at least two spades along with a doubleton diamond. That player can win the ♠A and shift to a diamond. Three rounds of diamonds, East ruffing the third, kills your club discard after you overruff. Now you are at the mercy of the club finesse. If the third diamond comes from East you have to decide whether to discard a club or ruff high. If you ruff high, you will need the club finesse. If you discard you need to find West with at least one more diamond. If West has one
more diamond, you won’t need the club finesse.
Given this unpleasant (but unlikely) scenario, it would have been better to play three rounds of heart immediately, hoping they lived. But don’t you dare take any credit if you played hearts before spades!
West leads the ♦J (denying a higher honor). East plays the ♦6, standard signals. (East–West are playing
Your decision not to convert 3NT to 4♠ is looking better and better, particularly with the ♦A K marked to your right. Plan the play.
First, it is important to work out the diamond position knowing East has the A–K. Given dummy’s diamond spots, it looks like West has led from J–10–x. The normal lead from J–10–x–x is low. Nor can have West have led from the J–10 doubleton. If so, East would have signaled with the ♦7 rather than the 6, not to mention East would have opened 2♦, weak. Figure West for the J–10–7 and go from there.
Since you cannot afford to give up the lead in spades, you must try for a total of at least seven tricks between clubs and hearts.
Plan A: Lead a club to the king and a club to the ace. If the ♣J has not appeared (your ninth trick), try a heart to the 10. If the 10 holds, cash the ♥K, return to the ♣Q and cash the ♥A Q for nine tricks. In addition, if the clubs are 3–3, you can still return to the ♠A in dummy to score the ♣10 for an overtrick. This is better than trying for four tricks in clubs by playing the ♣A, ♣Q and another club. If the clubs don’t come in, you do not have the wherewithal to take the heart finesse.
Plan B: Exit with a diamond at trick two. Assuming the opponents cannot cash more than four diamond tricks, you leave open the chance for a defensive error plus possible squeeze endings. In addition, you have not given up on taking seven tricks between clubs and hearts. Say the opponents cash four diamond tricks. You will discard two spades from your hand and three spades from dummy. West will also have to make two discards. Presumably West will discard spades and East will get out with a spade. (If he gets out with anything else, you have a claimer). Now you have further options. You can always fall back on Plan A or you might decide to try to squeeze West in spades and hearts or spades and clubs. Say West has 4–4 in the majors. Three rounds of clubs will force a heart discard and now the hearts are good no matter who has the jack. Similarly if West is 4–4 in the blacks, three rounds of hearts will squeeze West out of a club and now the clubs will run.
Clearly, it would help to be at the table if you elected Plan B.
So which plan is better? At matchpoints “A” is better because it allows for a possible overtrick thus beating the pairs in 4♠ making four. At IMPs “B” is better because it gives you more options while still allowing you to fall back on Plan A.