Board 5
Our side vulnerable
| ♠ A Q J 5 4 ♥ 4 3 ♦ A ♣ K Q 10 5 2 |
Two passes to me. I open with one spade, LHO bids two diamonds, partner bids two spades, and RHO passes.
Culbertson's rule for slam bidding states: If partner's perfect minimum gives you a laydown slam on normal breaks, you should invite. That's a useful rule for game-bidding as well. Here, all I need for game is the spade king and club jack, which is less than a perfect minimum. So I don't invite game; I just bid it. Everyone passes, and West leads the club ace.
| NORTH Robot ♠ 10 6 3 ♥ A J 10 8 6 ♦ K 10 3 ♣ 6 4 |
||
| SOUTH Phillip ♠ A Q J 5 4 ♥ 4 3 ♦ A ♣ K Q 10 5 2 |
| West | North | East | South |
| Robot | Robot | Robot | Phillip |
| |
Pass | Pass | 1 ♠ |
| 2 ♦ | 2 ♠ | Pass | 4 ♠ |
| (All pass) | |
|
|
There is a fair chance the lead is from a singleton. Even if it isn't, I doubt West has the club jack, so I will probably hook East for the jack at some point. I play the four from dummy; East plays the club three. There is no reason to let West know East played his lowest club, so I play the five.
West shifts to the five of diamonds—three—eight—ace. I could lead a heart to dummy, pitch a heart on the diamond king, and lead the spade ten for a finesse. But even if it wins, it’s not clear I’ve gained anything, since I won’t be able to re-enter dummy for the marked club finesse. If I have two finesses to take and I'm only going to be able to take one of them, I might as well take the one that's almost certain to work. So I'm inclined to play spades from my hand.
Will I regret that decision if East has king doubleton of spades and gives his partner a club ruff? If that happens, I have a trump left in dummy with which to ruff my last club, so I have the rest of the tricks. I lose the club ace, the spade king, and a ruff. Making four. If I take the spade finesse (assuming I lead the ten to do so), I take five spades, a heart, two diamonds, and two clubs. Also ten tricks. So even in that case, I break even playing spades from my hand.
I cash the spade ace—deuce—three—nine.
Should I lead a low spade to the ten or an honor? If East wins the spade king and shifts to hearts, I'd like to be able to draw the last trump and stay in dummy. So leading an honor looks better.
I lead the spade jack. West takes the king, and East pitches the heart deuce. Now that I know West has at least nine cards in spades and diamonds, the likelihood that the club ace was a singleton has gone up. If he has six diamonds, it was surely a singleton. He would not have lead from ace doubleton of clubs with a stiff heart. Could he be 4-2-5-2? That's possible, but the club ace would be a strange lead with that hand. A diamond, hoping to start a tap, would be a more attractive choice.
There is further evidence that I wouldn't have playing against humans: East's discard of the heart deuce. As I've noted previously, the robots tend to give count on their first discard, so the heart deuce is a strong indication West is 4-3-5-1.
Here is the current position. West holds two more spades and, presumably, all red cards.
| NORTH Robot ♠ 10 ♥ A J 10 8 6 ♦ K 10 ♣ 6 |
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| SOUTH Phillip ♠ Q 5 4 ♥ 4 3 ♦ -- ♣ K Q 10 2 |
If West shifts to a heart, I can win with the ace and pitch a heart on the diamond king. But I'm stuck with two club losers. I can't get back to dummy after drawing trump to take the club finesse. Maybe I can survive if West has both heart honors. Say he shifts to the heart king. I win, cash the spade ten, then, instead of taking my pitch, I ruff a low diamond, draw the last trump, and play a heart. West wins, and I have the rest whatever suit he returns.
What if West shifts to a low heart in the above position? If I'm right about the stiff club, I go down if I rise with the heart ace, so I might as well insert the jack. If West is being sneaky with both heart honors, I make an overtrick. If East wins, I just have to hope I'm wrong about the club break.
But West doesn't play a heart. He shifts to the diamond six. I win with dummy’s king, East plays the deuce, and I pitch the heart three. I cash the spade ten, ruff a diamond, draw the last trump, then play a heart to the ace for a club finesse. East began with five clubs as I had assumed, so I have to lose the last trick. Making four.
| NORTH Robot ♠ 10 6 3 ♥ A J 10 8 6 ♦ K 10 3 ♣ 6 4 |
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| WEST Robot ♠ K 8 7 2 ♥ K Q 7 ♦ Q 7 6 5 4 ♣ A |
EAST Robot ♠ 9 ♥ 9 5 2 ♦ J 9 8 2 ♣ J 9 8 7 3 |
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| SOUTH Phillip ♠ A Q J 5 4 ♥ 4 3 ♦ A ♣ K Q 10 5 2 |
100%! No one else made this game? Why was this deal so hard?
Some declarers got a diamond shift at trick two, then went down because they used their heart entry to take a spade finesse. But not all declarers got a diamond shift. Some Wests shifted to the heart king. Why would West shift to a diamond sometimes and a heart at other times? Apparently West shifted to a diamond if declarer played the club five at trick one but a heart if he played the club deuce. While the club five is in principle the correct play, it's hard to see how it mattered. Most likely it was simply a butterfly effect. Or perhaps the bridge gods chose to bestow an award for careful play.
How should South proceed after a heart shift at trick two? You could try an immediate spade finesse, but winning and leading a club to the ten gives you two chances instead of just one. If West doesn't ruff, you're in good shape. You can cash the diamond ace and lead another club. If West ruffs in with the spade king and cashes a heart, you have the rest. If he doesn't, you can pitch your heart on the diamond king and take the spade finesse. You might wind up making six.
As it happens, West ruffs when you lead a club to the ten. He will then cash the heart queen and play a diamond, sticking you in your hand. You can now take your second chance: ruff a club to dummy and try the spade finesse. You won't be able to pick up king third, since West will ruff in when you play a club, forcing you to overruff with the ten. But once East shows up with five clubs, he is unlikely to have three spades anyway.
Since the club ace is singleton and the spade king is offside, this line doesn't work. There are other lines that do, but I don't see any reason to choose one of them. I 'm sure I would have gone down after a heart shift, so most of the credit for this result belongs to that butterfly.
I'm still in first place, with 78%.
What do you think of the ace of clubs lead?
ReplyDeleteIt doesn't seem like a good idea. Partner doesn't have much, so it's unlikely he has an entry to give you a ruff with. You're better off hoping to play the ace on one of declarer's club honors. I would lead a diamond myself.
DeleteI played the C2 and got the HK shift. I did run the ST, and got both chances in as expected - W has to now cash the HQ to beat me, and he doesn't.
ReplyDeleteWe know the bots decide their play by randomly generating deals consistent with the information known at the time, solving each one double-dummy, and making the play that scores the best on average. It also seems that BBO seeds the random-number-generator based on a hash of the cards played so far (so that different humans who made the same plays get the exact same bot plays out).
ReplyDeleteSo, the conclusion is that you have the Random-Set-Of-Deals-After-C2 and a different Random-Set-Of-Deals-After-C5. Since a different play depending on set, we can conclude that per DD analysis, the two shifts are nearly equal in score.
That's probably the right explanation. But I wonder. Suppose, for example, West assumes his partner would play second lowest from six. (Not that I have any reason to believe that's the case--just for the sake of argument.) When I play the deuce, East can't have six clubs; when I play the five, he can. In that case, my choice of the five has a direct effect on the deals he generates, not just an unpredictable effect as a random seed. And perhaps if you include deals where East has six clubs, a diamond shift turns out to be better. It would be more satisfying if my play worked for the right reason. But that's probably just a fantasy.
Delete