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What they don’t know
I played this deal online. Take my seat as South:
♠ 7 6 5 ♥ A K 10 7 5 4 ♦ A 10 8 ♣ 3
At matchpoints, with neither side vulnerable, you open 1♥. (This hand is way too strong for a weak two-bid.) Left-hand opponent bids 2♥ – a Michaels cuebid showing spades and one of the minor suits. Your partner bids 3♣. What’s that?
Experienced partnerships have methods – usually artificial – to deal with two-suited interference. This might be some sort of good heart raise, but there was no discussion/agreement. In that case, probably it should be natural.
Is it forcing? This isn’t clear. If partner had a good hand, he could have started with a double (card-showing), so he might mean 3♣ as natural and non-forcing. RHO doubles 3♣. Whatever partner has in mind, it seems prudent to rebid the decent six-card suit. This probably wouldn’t be a good dummy in 3♣ doubled. Surprisingly, your 3♥ ends the auction and you play it there with the lead of the ♣4.
It looks like you have to lose two spade tricks, two diamonds and, if hearts are 3–2, one heart. That’s down one. Can you do anything about it?
Perhaps you can ruff a diamond in dummy? The ♣4 – combined with the auction – sure looks like a singleton, so a trick-one finesse makes no sense. You win the ♣A and take stock. To ruff a diamond in dummy, you would have to give up the lead. The defense can then badger you with ♠A, ♠K and a spade ruff in the East (you know from the Michaels bid that a ruff is looming), then a club through you, LHO poised to overruff.
Is there an alternative? If you draw trumps first, you are sure to go down, barring an unlikely ♥Q J doubleton. After you draw trump, you have to lose two diamonds and two spades (and the trump trick). Fortunately, hearts rate to be 3–2. Why? LHO has a presumed singleton club and if he is 5–5, that means a doubleton heart.
Enough stalling. I recommend playing a diamond toward your hand at trick two. The plan is to insert the 10 and when this loses, LHO will be on the spot. You know he can defeat you, but he doesn’t. If he has both the ace-king in spades (which he might have led from), he won’t have a problem. But if he has only one of them, how will he know what to do? Let’s look at the full Real Deal:
After winning the ♣A at trick one, declarer played a diamond to the 3, 10 and jack. Look at poor West’s problem. He didn’t want to lead from his ♠K – he didn’t know who had the ♠A. He didn’t want to play from his ♥Q – it wouldn’t have helped – so he played a seemingly safe high diamond. Now, declarer won the ace, ruffed a diamond and played the top trumps to make nine tricks.
True, the defense lost its way. Perhaps East should play the ♣J at trick one and maybe that should be suit preference, suggesting a high spade card. Still, relying on a defensive error is often a desirable line of play, and in this case, it produced plus 140 and an excellent matchpoint score.