Thursday, January 29, 2009

Avoiding pitfalls

It's so easy to make mistakes when defending a bridge contract. The deal shown below was played online on OKbridge last Saturday in their 5:30 ACBL IMP tournament. It was deal #1:

A 9 8 7
9 8 6
9 8 2
J 5 2
Q 10 3 2 6 5
K Q 10 7 J 5 3 2
A K J 6 Q 10 7 5 4
10 7 6
K J 4
A 4
3
A K Q 9 8 4 3

Usually South opened 1 and West doubled. There were many different auctions from that point, but 3, 4 and 5 were common contracts. In almost every case, West led a high diamond, and then paths diverged. Let's see what happened when North-South were in 5.

In looking at the play records, I see that often West continued with another high diamond and the contract was makeable. Declarer ruffs, draws trump and leads the K and then the jack. After West covers (ducking is no better), declarer leads another spade from dummy, conceeding a trick to the 10. But now the 8 is high and the J is an entry to discard a losing heart. Several declarers found this line, so kudos to them. It's obviously the best shot because West is far more likely to hold the Q than East. A few declarers improved on this by taking a backwards finesse. They led the J first. After it was covered, they then finessed East for the 10. This cannot cost a trick and gains when East has 10 x x.

In several instances, however, West shifted to the K at trick two. Now if declarer plays as described in the paragraph above, West can cash a heart trick when in with the spade. At several tables, however, when he was in, he couldn't tell whether to try and cash the heart or the diamond. Good carding by East and an alert West will overcome this pitfall, but online players don't always card well.

After the shift to the K, however, declarer can take a different line. He can run all the clubs but one, and reduce the hands to this:

A 9 8
9 8
---
---
Q 10 3 6
Q 10 J 3
--- Q 10
--- ---
K J 4
4
---
3

To reach this position, West must have watched the cards played by East and known that it was safe to discard his high diamonds. When he led the K at trick two, what did East play? East must play an encouraging card -- the 5 if playing standard carding and the 2 if playing upside down.

Now South plays his last club, and what does West do? If he discards a spade, South has no spade losers, so he must discard a heart. But which one? If he discards the 10, South can read the position and lead his 4 to endplay West. When West wins, he has to lead a spade, giving up his trick in that suit. To avoid the endplay, West has to discard his Q. Now if South exits with a low heart, East can overtake the 10 with his jack and cash one or two diamonds.

See how many pitfalls there are? See how important accurate carding is? See how high the level of trust must be? Would you and your favorite partner avoided all the traps?

Thanks to Xwing who showed me this deal. You can see the bidding and play of this intersting deal at each of 65 tables if you click here.

2 comments:

  1. What's interesting is that in the end position, the defenders have to be careful! If declarer throws a spade from dummy, cashes sA, and exits a heart, East has to rise with the hJ to push a heart through. Because dummy gets squeezed out of its seemingly idle 3rd spade, the contract cannot be made.

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