Great stuff, thanks. I'd play for the drop because that also allows me to ruff a diamond first. Some care is needed to draw hearts first and ensure entries
Six months late but the odds of a 3-3 break or Jx is 36% + 1/3 * 62% which is rough 57%, so better to play for the drop. But playing off a top diamond and going for a ruff works when diamonds break 3-3 and trumps are no worse than 4-2, or when diamonds are 4-2 and the person with the doubleton diamond has 3 or 4 trumps so I think that's better.
Ruffing a diamond seems better since you should play for the drop anyways. If diamonds are 3-3 it doesn't hurt to ruff a diamond. If diamonds are 4-2 then the ruff trades your diamond loser for a spade loser. But if the hand ruffing has long spades they may end up giving up the JS in exchange for ruffing. If the 6S wins the trick, you can ruff a club back to hand and draw trumps from the top. I think it's very common for W to have 4S here since from the play so far they likely have a doubleton diamond (T9X or T9xx doesn't seem like a very good lead against a slam) and seem to have 2-3 hearts from the JH showing up early. This means they have eight or nine black cards, and a six card club suit is somewhat unlikely given that they might have opened 3C or 1C (especially if they have something like XX QJX TX AQJXXX or even JXX JX TX AQJXXX. If they have nine black cards and don't have six clubs they'll have at least four spades making it very likely you have one trump loser and need to avoid a diamond loser to make. Note that the finesse gets even worse as W is more likely to have more spades since the odds of the Jack being onside aren't 50/50 if you know W has 4S and E has 2S for example.
It is 15:10 (3:2) odds on to play for drop. Drop wins in 15 case: 5 cases of doubleton J off-side in 2-4 split + 10 cases of off-side J in 3-3 split (while finnesse fails) Finnesse wins in 10 cases of 4 cards to J on-side in 2-4 split (while drop fails) In all other cases they either both fail or succeed.
minor correction there is 1 other case of finnesse win - singleton 9 off-side therefore it should be [drop15 : finnesse 11] odds on for drop Also, this is IMP valuation. In MP where going extra down matters (ie. 1off wins against 2off) it is [drop16 : finnesse 15] marginal
Beter chance imho is playing in trick 2 dia Q followed by a small dia ruff. Wins with dia 3-3 or trumps 3-3, but also with dia 4-2 & short dia with 4-card trump.
Great lesson Curt. One question - I thought you should always cash your ace asap when defending v a slam, even if you don't have a likely trump trick? And thereafter hope that you or your partner can get a ruff before declarer draws all the trumps.
Often the decision to lead an ace against a slam contract depends on the format. If you are playing matchpoints and believe your opponents are in a good slam, it is often wise to take the one trick you have coming. Playing IMPs where the overtrick is negligible, you might find a different lead for a better chance to perhaps beat the slam, as laying down an ace could give declarer the 12th trick.
Poor play by W, leading diamonds - the second suit called by South in a slam shaped hand!! But E was doubly stupid to offer his K hearing the same bidding!!! :(
Great stuff, thanks. I'd play for the drop because that also allows me to ruff a diamond first. Some care is needed to draw hearts first and ensure entries
Six months late but the odds of a 3-3 break or Jx is 36% + 1/3 * 62% which is rough 57%, so better to play for the drop.
But playing off a top diamond and going for a ruff works when diamonds break 3-3 and trumps are no worse than 4-2, or when diamonds are 4-2 and the person with the doubleton diamond has 3 or 4 trumps so I think that's better.
Ruffing a diamond seems better since you should play for the drop anyways. If diamonds are 3-3 it doesn't hurt to ruff a diamond. If diamonds are 4-2 then the ruff trades your diamond loser for a spade loser. But if the hand ruffing has long spades they may end up giving up the JS in exchange for ruffing. If the 6S wins the trick, you can ruff a club back to hand and draw trumps from the top. I think it's very common for W to have 4S here since from the play so far they likely have a doubleton diamond (T9X or T9xx doesn't seem like a very good lead against a slam) and seem to have 2-3 hearts from the JH showing up early. This means they have eight or nine black cards, and a six card club suit is somewhat unlikely given that they might have opened 3C or 1C (especially if they have something like XX QJX TX AQJXXX or even JXX JX TX AQJXXX. If they have nine black cards and don't have six clubs they'll have at least four spades making it very likely you have one trump loser and need to avoid a diamond loser to make. Note that the finesse gets even worse as W is more likely to have more spades since the odds of the Jack being onside aren't 50/50 if you know W has 4S and E has 2S for example.
It is 15:10 (3:2) odds on to play for drop.
Drop wins in 15 case: 5 cases of doubleton J off-side in 2-4 split + 10 cases of off-side J in 3-3 split (while finnesse fails)
Finnesse wins in 10 cases of 4 cards to J on-side in 2-4 split (while drop fails)
In all other cases they either both fail or succeed.
minor correction
there is 1 other case of finnesse win - singleton 9 off-side
therefore it should be [drop15 : finnesse 11] odds on for drop
Also, this is IMP valuation. In MP where going extra down matters (ie. 1off wins against 2off) it is [drop16 : finnesse 15] marginal
Beter chance imho is playing in trick 2 dia Q followed by a small dia ruff. Wins with dia 3-3 or trumps 3-3, but also with dia 4-2 & short dia with 4-card trump.
Not trick 2. You need to get your club loser away first.
Great lesson Curt. One question - I thought you should always cash your ace asap when defending v a slam, even if you don't have a likely trump trick? And thereafter hope that you or your partner can get a ruff before declarer draws all the trumps.
Often the decision to lead an ace against a slam contract depends on the format. If you are playing matchpoints and believe your opponents are in a good slam, it is often wise to take the one trick you have coming. Playing IMPs where the overtrick is negligible, you might find a different lead for a better chance to perhaps beat the slam, as laying down an ace could give declarer the 12th trick.
Thanks Curt, good to know!@@curtsoloff4519
Poor play by W, leading diamonds - the second suit called by South in a slam shaped hand!! But E was doubly stupid to offer his K hearing the same bidding!!! :(
3-3 is 36%
Finesse 10
Finessing 10 slightly better odds