A Useful Convention

Playing in a regional KO match, I'm the dealer with both vulnerable. I pick up a pretty good hand,

AKQ1098

8752

K6, and get to open 1

. The opponents are silent, and partner bids 2

. We play 2/1s as game forcing, so we are in the slam zone. I have lots of choices here, but probably the best is to splinter with 3

. That should allow partner to evaluate his hand and aim us towards 3NT, 5

, or 6

. Over my 3

, partner bids 4

, and I don't know yet what his plan is; we do not play fast arrival, so 5

would have been a slam try showing good diamonds, and 4

is ambiguous. In any case, I have an easy 4

bid. Partner bids 4

, and I have a problem.

First off, partner has made a clear slam try. If he just wanted to play game in diamonds, he would have signed off in 5. So now that I know he has planned this sequence, I also know that he has no club control; he would have bid 4 rather than 4 with one. It's possible that partner has the Q, but it's also likely that we need to play the hand from my side to protect the Kx. Since a grand slam isn't in the picture (we're off the A), I could just bid 6; surely that suit is playable. If the hearts run, we have six hearts, five diamonds, and the A for 12 tricks. Partner might, however, have a singleton or void heart and a very good hand otherwise, say AKx x AKQxxxx xx. In that case, I'd like him to correct 6 to 6NT. So I need to pick off the notrump first. The only way I can do that is to bid Blackwood! I don't care how many aces he has; in fact, if he has two key cards and the Q, I'm going to have to bid slam knowing we are off two key cards. I hope they are the A and K.

Let's make a plan. If partner bids 5, I'm stuck. That'll give him (I hope) something like AKx x AQJxxx Qxx. Without the lower black honors, he'd probably not make a slam try, so 6 is probably OK. If partner bids 5, I have no choice but to pass; we have a sure diamond loser and a club loser. If partner bids 5...he can't. He can have neither one nor four key cards. If partner bids 5, which seems likely, then my plan will bear fruit. I'm going to jump to 6. If he has a hand suitable for play in hearts, he can pass, and if he doesn't, he can bid 6NT, which will then be played from my side.

As expected, partner responds 5 to 4NT, showing zero or three key cards in diamonds. I jump to 6. Partner thinks about this for a few seconds and passes. The opening lead is a spade and I see A973 J3 AKQ96 102. I draw trumps, and when diamonds break, claim twelve tricks for +1430. At the other table, they play the prosaic 6. Luckily for us, the A was offside, so we win 17 IMPs on the board. Since we won the match by 14, that's very fortunate. If the A had been onside, we would have won only 2 IMPs (hopefully our teammate would have led his A) and lost the match by one.

The funny thing about this hand is that I didn't bid Blackwood to stay out of a slam if we had too few aces; I was pretty sure we had plenty. It was just to make sure notrump was played from the right side. I don't recall seeing that before.