Simulation 8Z15   Main

# Stayman or Pass?

by Richard Pavlicek

Suppose North opens 1 NT (15-17) in first seat, East passes, and you have this hand:

 West NORTH1 NT EastPass South? You (South) J 7 6 3 J 8 7 4 7 4 A Q 5

Kevin O’Dea (Ireland) asks, “If you bid 2 Stayman intending to pass opener’s 2 or 2 , will your matchpoint score, on average, be better or worse than passing 1 NT?”

I would think better but can’t offer a definite answer. Trying to solve this by theoretical calculation would be a numerical nightmare, if even possible. The only practical solution is to run a simulation, so we’ll consult Madame Zoltar for the answer.

Kevin suggests two options: (A) Pass 1 NT, or (B) bid 2 then pass 2 or 2 . For interest sake I will include a third: (C) Bid 2  then raise or 2  to invite game. Note that Options B and C both require a 2 NT follow-up over 2  when opener denies a major.

The final contract for Options B and C will vary according to the presence of a major fit and opener’s strength. More specifically, Option B will have North declaring 2 , 2 , 2 NT or 3 NT; and Option C will have North declaring 2 NT, 3 , 3 , 3 NT, 4  or 4 . Determining the strain is easy; either North has a major or he doesn’t, and with both he bids 2 . My criterion for a maximum will be 17 revalued points, a better yardstick than simply HCP, as it includes some hands of 16 HCP but rejects others.

For a simulation I created 10,000 random deals with the South hand fixed. North: 15-17 HCP; balanced; 5-card major allowed if doubleton is J-x or better. East was constrained not to have any appropriate action (bid or double) over 1 NT. No constraints were placed on West (no turn yet).

Results are shown below. Trick Average shows the average number of tricks won by declarer. Make Percent shows how often the contract is made (including with overtrick) and Overtrick Percent how often an overtrick is made. The second table compares the options directly, with the better option leftmost. Net W-L (matchpoints or board-a-match verdict) counts +1 for a win and -1 for a loss. Net Score and Net IMPs are calculated twice, first with declarer nonvul (green) then with declarer vul (red). Plus values show the net gain over 10,000 deals.

As predicted, Option B is the winner at matchpoints, and perhaps surprisingly, at IMPs as well. In fact the only loss for Option B is at total points vulnerable to Option C, but this can be ignored with the obsolete scoring method. The case for runner-up is a mixed bag: Option C tops Option A at total points and IMPs vulnerable but loses at matchpoints and IMPs nonvulnerable. Enlightening or bewildering [pick one].

Results for 10,000 Deals
OptionTrick AverageMake PercentOvertrick Percent
A. 1 NT N7.891789.8767.11
B. ?? N8.661977.0550.21
C. ?? N8.661952.3913.66

ComparisonNet W-LNet ScoreNet IMPsNet ScoreNet IMPs
B. ?? N vs. A. 1 NT N+2488+132920+4389+218970+6108
B. ?? N vs. C. ?? N+1174+88340+2970-58460+34
C. ?? N vs. A. 1 NT N-547+44580-726+277430+3104

### Actual Deals

Below are 100 of the 10,000 deals, including the first 20, last 20, and 60 in-between with the greatest IMP gains (20 for each option). Numbers after each contract show the tricks won by declarer with double-dummy play all-around. A plus sign indicates the best result.

 1. K 10 8 K Q 5 A K 10 6 5 3 2 A 2 3 2 Q 9 8 3 2 J 10 7 6 Q 9 5 4 A 10 9 6 J K 9 8 4 1 NT N → 8 +2 NT N → 8 +2 NT N → 8 + J 7 6 3 J 8 7 4 7 4 A Q 5

 2. A K 8 2 10 3 2 A K 6 K 6 4 10 4 K 6 5 J 8 5 3 2 7 3 2 Q 9 5 A Q 9 Q 10 9 J 10 9 8 1 NT N → 82 N → 9 +4 N → 9 J 7 6 3 J 8 7 4 7 4 A Q 5

 3. A 9 K 10 2 A K Q 10 5 J 4 2 4 2 A Q 9 5 8 6 3 2 9 6 3 K Q 10 8 5 6 3 J 9 K 10 8 7 1 NT N → 103 NT N → 10 +3 NT N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 4. A 9 A Q 10 6 2 Q 10 9 K J 3 K Q 8 4 K J 8 5 2 10 9 7 6 10 5 2 9 5 3 A K 6 3 8 4 2 1 NT N → 92 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 5. A K 2 K Q J 10 5 K J 10 6 4 10 9 5 A 10 9 2 9 8 6 3 2 2 Q 8 4 6 5 3 A K Q 9 8 7 3 1 NT N → 7 +3 NT N → 73 NT N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 6. K 8 5 A Q 6 3 2 K J K 3 2 10 9 4 K 10 9 A 10 3 9 8 6 4 A Q 2 5 Q 9 8 6 5 2 J 10 7 1 NT N → 62 N → 9 +3 N → 9 + J 7 6 3 J 8 7 4 7 4 A Q 5

 7. A Q 5 K 6 2 A Q 9 8 5 J 8 8 A 10 9 5 3 K J 10 6 10 4 2 K 10 9 4 2 Q 3 2 K 9 7 6 3 1 NT N → 9 +2 NT N → 9 +2 NT N → 9 + J 7 6 3 J 8 7 4 7 4 A Q 5

 8. K 10 5 A 10 9 K J 2 K J 8 7 A Q 9 2 K 5 2 9 3 10 4 3 2 8 4 Q 6 3 A Q 10 8 6 5 9 6 1 NT N → 7 +2 NT N → 72 NT N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 9. K 8 4 K 2 K Q J 5 2 K 7 4 A Q 10 9 2 10 9 5 A 3 J 9 8 5 A Q 6 3 10 9 8 6 10 6 3 2 1 NT N → 8 +2 NT N → 8 +2 NT N → 8 + J 7 6 3 J 8 7 4 7 4 A Q 5

 10. K 10 A 10 6 5 A J 10 2 K 10 2 A 8 4 2 K K Q 9 8 5 9 7 4 Q 9 5 Q 9 3 2 6 3 J 8 6 3 1 NT N → 92 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 Simulation 8Z15   Main Top   Stayman or Pass?

 11. K Q 10 2 A 2 K Q 3 2 J 8 2 9 8 5 4 K 9 6 3 A J 10 6 9 A Q 10 5 9 8 5 K 10 7 6 4 3 1 NT N → 82 N → 9 +3 N → 9 + J 7 6 3 J 8 7 4 7 4 A Q 5

 12. A Q 9 5 A Q A 10 8 3 J 10 7 4 K 9 6 5 K 9 6 5 K 8 6 2 K 10 8 2 10 3 2 Q J 2 9 4 3 1 NT N → 72 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 13. K Q 8 5 Q 6 A K 8 J 10 7 3 A A K 3 2 6 3 2 K 9 6 4 2 10 9 4 2 10 9 5 Q J 10 9 5 8 1 NT N → 8 +2 N → 83 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 14. Q 10 5 A K 9 K Q 8 6 2 J 8 A K 9 8 10 6 5 J 10 10 7 6 2 4 2 Q 3 2 A 9 5 3 K 9 4 3 1 NT N → 7 +2 NT N → 72 NT N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 15. A 5 2 A 5 3 A K Q 10 7 4 2 K 10 9 10 2 J 9 6 5 3 J 9 8 Q 8 4 K Q 9 6 8 2 K 10 6 3 1 NT N → 8 +3 NT N → 83 NT N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 16. K 9 A K 5 J 9 8 3 2 K J 8 A Q 5 2 6 3 2 K Q 5 10 6 4 10 8 4 Q 10 9 A 10 6 9 7 3 2 1 NT N → 7 +2 NT N → 72 NT N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 17. A K 9 K Q 10 8 5 2 K J 7 2 Q 8 4 A 9 6 3 J 10 9 6 3 8 10 5 2 5 2 A K Q 10 9 6 4 3 1 NT N → 7 +2 NT N → 72 NT N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 18. K Q Q 10 3 K Q J 9 3 K 4 2 9 5 2 A 2 A 2 J 9 8 7 6 3 A 10 8 4 K 9 6 5 10 8 6 5 10 1 NT N → 9 +2 NT N → 9 +2 NT N → 9 + J 7 6 3 J 8 7 4 7 4 A Q 5

 19. K 10 5 K Q 5 A 9 6 2 K 3 2 Q 8 2 6 3 2 J 5 3 J 7 6 4 A 9 4 A 10 9 K Q 10 8 10 9 8 1 NT N → 8 +2 NT N → 8 +2 NT N → 8 + J 7 6 3 J 8 7 4 7 4 A Q 5

 20. A 9 4 A K 10 5 2 A J 6 J 8 K 8 6 3 K Q 9 8 2 K 7 3 2 Q 10 5 2 Q 9 10 5 3 10 9 6 4 1 NT N → 102 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 Simulation 8Z15   Main Top   Stayman or Pass?

 24. Q 10 9 A Q 6 5 3 A J K 4 3 A 8 2 2 K Q 9 6 5 3 9 8 7 K 5 4 K 10 9 10 8 2 J 10 6 2 1 NT N → 52 N → 9 +4 N → 9 J 7 6 3 J 8 7 4 7 4 A Q 5

 221. K 2 A Q 9 3 2 K 9 3 K J 2 A Q 9 5 10 5 J 6 5 10 9 8 4 10 8 4 K 6 A Q 10 8 2 7 6 3 1 NT N → 52 N → 9 +4 N → 9 J 7 6 3 J 8 7 4 7 4 A Q 5

 366. A K Q 9 8 Q 5 2 K 5 K 10 2 4 K 9 6 Q J 10 8 6 2 9 6 4 10 5 2 A 10 3 A 9 3 J 8 7 3 1 NT N → 52 N → 9 +4 N → 9 J 7 6 3 J 8 7 4 7 4 A Q 5

 431. Q 5 4 K Q 10 5 A K 5 K 8 2 K A 9 J 6 3 2 J 10 9 7 6 3 A 10 9 8 2 6 3 2 Q 10 9 8 4 1 NT N → 8 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 491. A K 10 9 5 K 10 9 K 10 K 8 7 Q 8 2 A Q 5 3 J 8 6 6 4 3 4 6 2 A Q 9 5 3 2 J 10 9 2 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 700. A K Q 8 Q 9 6 K 8 K 10 4 2 10 9 4 2 A K 10 9 3 J 9 7 6 5 5 3 2 A Q J 10 6 5 2 8 3 1 NT N → 42 N → 9 +4 N → 9 J 7 6 3 J 8 7 4 7 4 A Q 5

 829. A K Q K Q 9 6 3 J 10 10 9 8 9 2 — K Q 9 6 5 3 K J 7 4 3 10 8 5 4 A 10 5 2 A 8 2 6 2 1 NT N → 42 N → 8 +3 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 905. A K A K 10 5 K 10 6 3 10 4 2 Q Q 9 6 3 2 J 5 K J 9 7 3 10 9 8 5 4 2 — A Q 9 8 2 8 6 1 NT N → 8 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 925. K Q 10 9 5 K 10 5 A 9 5 K 10 A 8 Q 3 Q 10 8 6 3 2 4 3 2 4 2 A 9 6 2 K J J 9 8 7 6 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 1714. A Q 5 2 K Q Q 5 2 K J 6 4 K 9 8 4 9 3 2 A K 10 9 8 3 — 10 A 10 6 5 J 6 10 9 8 7 3 2 1 NT N → 7 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 Simulation 8Z15   Main Top   Stayman or Pass?

 2018. A K Q 4 6 5 2 K 5 K 10 4 3 10 9 8 2 K 3 J 8 3 2 9 6 2 5 A Q 10 9 A Q 10 9 6 J 8 7 1 NT N → 42 N → 8 +3 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 2047. K Q 2 A K Q 2 10 8 K 6 4 3 10 5 9 3 K Q J 9 6 3 J 9 2 A 9 8 4 10 6 5 A 5 2 10 8 7 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 2119. A K Q 8 K Q 3 8 6 K 6 3 2 9 5 A 9 6 5 Q J 2 J 10 7 4 10 4 2 10 2 A K 10 9 5 3 9 8 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 2207. 10 5 4 K Q 9 2 K Q J K J 10 A 9 10 5 A 10 9 8 6 5 3 9 3 K Q 8 2 A 6 3 2 8 7 6 4 2 1 NT N → 8 +2 N → 63 N → 6 J 7 6 3 J 8 7 4 7 4 A Q 5

 2462. K 8 5 2 K 9 3 A Q J 2 K 10 — A 2 10 9 8 3 J 9 8 7 6 4 2 A Q 10 9 4 Q 10 6 5 K 6 5 3 1 NT N → 8 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 2477. A K Q 9 5 Q 10 3 K 9 K 10 4 8 2 K 9 6 5 10 8 2 J 8 7 6 10 4 A 2 A Q J 6 5 3 9 3 2 1 NT N → 52 N → 9 +4 N → 9 J 7 6 3 J 8 7 4 7 4 A Q 5

 2515. A Q 10 9 8 A Q 9 Q 8 K 4 2 5 4 2 K 10 3 2 A J J 10 8 7 K 6 5 K 10 9 6 5 3 2 9 6 3 1 NT N → 62 N → 114 N → 11 + J 7 6 3 J 8 7 4 7 4 A Q 5

 2722. A K Q 10 8 K 5 2 J 8 5 K 9 9 3 A K Q 10 6 3 2 J 10 3 2 5 4 2 A Q 10 9 6 9 8 7 6 4 1 NT N → 42 N → 8 +4 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 2848. A K 2 A Q 3 2 6 5 K J 8 6 9 8 4 K 10 5 K J 9 2 9 7 3 Q 10 5 9 6 A Q 10 8 3 10 4 2 1 NT N → 82 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 2897. K Q 8 A 6 5 2 K J 9 6 K 4 9 2 K 10 9 3 8 5 2 J 10 8 2 A 10 5 4 Q A Q 10 3 9 7 6 3 1 NT N → 7 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 Simulation 8Z15   Main Top   Stayman or Pass?

 3061. A K 8 2 A K 5 2 Q 6 J 9 7 Q 5 4 3 A K J 10 9 8 5 3 K 10 9 Q 10 9 6 2 10 8 6 4 3 2 1 NT N → 52 N → 9 +4 N → 9 J 7 6 3 J 8 7 4 7 4 A Q 5

 3175. K Q 9 5 2 K Q 9 Q 2 K 8 4 4 A 10 6 K J 10 9 8 6 5 9 3 A 10 8 5 3 2 A 3 J 10 7 6 2 1 NT N → 42 N → 8 +3 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 3672. A K 9 8 5 A 10 6 Q 2 K 10 7 Q 10 2 K 5 3 2 J 5 9 8 6 3 4 Q 9 A K 10 9 8 6 3 J 4 2 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 3866. K Q A K 6 3 Q J 8 10 9 7 2 A 10 9 8 4 2 — K 9 5 2 K 8 4 5 Q 10 9 5 2 A 10 6 3 J 6 3 1 NT N → 7 +2 N → 63 N → 6 J 7 6 3 J 8 7 4 7 4 A Q 5

 3888. A Q 5 4 A Q 6 10 6 K J 8 7 K 10 9 8 2 10 5 A K Q 9 6 4 — K 9 3 2 J 8 5 3 2 10 9 3 2 1 NT N → 7 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 3939. A K Q 2 K Q 10 6 Q J 3 9 6 9 5 A 5 6 5 2 K J 8 7 4 2 10 8 4 9 3 2 A K 10 9 8 10 3 1 NT N → 52 N → 9 +4 N → 9 J 7 6 3 J 8 7 4 7 4 A Q 5

 4025. K 10 4 2 A K 10 Q J 10 K 10 8 Q 8 9 6 3 6 3 J 9 6 4 3 2 A 9 5 Q 5 2 A K 9 8 5 2 7 1 NT N → 7 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 4034. A K 5 2 K 3 Q J 8 3 K J 8 8 Q 6 5 A 2 10 9 7 6 4 3 2 Q 10 9 4 A 10 9 2 K 10 9 6 5 — 1 NT N → 7 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 4293. A K 4 2 A 9 2 K J 10 9 J 9 Q 10 9 5 K Q 10 6 5 3 K 10 2 8 3 A Q 8 6 5 2 8 7 6 4 3 1 NT N → 7 +2 N → 63 N → 6 J 7 6 3 J 8 7 4 7 4 A Q 5

 4385. K 10 Q 10 5 3 2 A K 2 K 10 4 A 9 4 A Q J 8 6 5 3 J 6 3 Q 8 5 2 K 9 6 10 9 9 8 7 2 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 Simulation 8Z15   Main Top   Stayman or Pass?

 4457. A Q 8 5 4 A Q J 6 3 K 9 8 9 2 K 10 9 6 5 Q 9 J 7 4 2 K 10 3 2 A K 10 8 5 2 10 6 3 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 4551. A 10 9 K Q 10 6 3 K 10 K 3 2 K Q 4 A 5 2 6 3 2 J 9 8 4 8 5 2 9 A Q J 9 8 5 10 7 6 1 NT N → 52 N → 9 +4 N → 9 J 7 6 3 J 8 7 4 7 4 A Q 5

 4945. A Q 9 5 2 A 10 2 K 10 K 4 2 10 4 Q 9 5 A J 9 5 3 10 9 3 K 8 K 6 3 Q 8 6 2 J 8 7 6 1 NT N → 82 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 5203. A K Q 10 K Q 6 3 2 K 10 7 2 9 8 5 9 5 2 K 10 5 9 8 6 4 4 2 A 10 3 A Q J 9 8 6 J 3 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 5219. A 9 A 6 5 2 K Q 6 K 7 4 2 K 10 4 2 K Q 10 9 3 A J J 8 Q 8 5 — 10 9 8 5 3 2 10 9 6 3 1 NT N → 8 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 5478. A Q 10 9 5 A Q 3 J 9 8 K 4 8 2 K 10 2 10 2 J 10 8 7 6 3 K 4 9 6 5 A K Q 6 5 3 9 2 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 5719. A K 8 5 K 9 K Q 9 J 9 7 2 — A 10 6 5 A 10 6 5 K 10 8 6 4 Q 10 9 4 2 Q 3 2 J 8 3 2 3 1 NT N → 8 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 5752. K Q 10 5 4 A Q 9 K 5 K 9 2 A 9 2 K 2 10 9 3 J 10 7 6 3 8 10 6 5 3 A Q J 8 6 2 8 4 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 5756. K Q 10 4 A K Q 5 Q J 2 6 2 9 5 2 9 2 10 9 8 5 K 10 7 3 A 8 10 6 3 A K 6 3 J 9 8 4 1 NT N → 52 N → 9 +4 N → 9 J 7 6 3 J 8 7 4 7 4 A Q 5

 5917. Q 9 2 A K Q 5 J 9 6 K 7 3 A 10 5 10 K Q 10 8 5 3 2 10 4 K 8 4 9 6 3 2 A J 9 8 6 2 1 NT N → 42 N → 8 +3 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 Simulation 8Z15   Main Top   Stayman or Pass?

 6508. K Q 9 4 A K 10 5 J 10 9 K 4 A 10 8 5 3 A Q 8 5 J 10 9 2 2 Q 9 6 2 K 6 3 2 8 7 6 3 1 NT N → 8 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 6700. A 9 4 A K Q 6 3 K J 7 6 2 K Q 10 8 5 10 2 9 6 5 K 10 8 2 9 5 A Q 10 8 3 2 J 9 4 3 1 NT N → 7 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 6885. A 9 5 K Q 5 3 2 K 6 K 3 2 K 10 8 2 A 10 6 Q 10 8 10 9 8 Q 4 9 A J 9 5 3 2 J 7 6 4 1 NT N → 42 N → 8 +3 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 7016. Q 10 5 2 A K 10 9 Q J 10 K 3 A K 9 8 4 2 A 9 8 2 10 7 6 — Q 6 5 3 K 6 5 3 J 9 8 4 2 1 NT N → 7 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 7032. A K 9 K Q 10 9 6 3 K J 9 8 10 8 5 2 6 Q J 10 9 8 5 10 2 Q 4 A 5 3 2 A K 2 7 6 4 3 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 7422. A K 9 A Q 9 5 9 5 K 10 6 4 Q 10 2 A K Q J 8 6 3 2 J 7 10 8 5 4 2 K 6 3 10 9 8 3 2 1 NT N → 52 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 7722. Q 8 5 2 A Q 9 2 K 2 K J 7 A K 9 4 6 5 3 J 9 9 4 3 2 10 K 10 A Q 10 8 6 5 3 10 8 6 1 NT N → 42 N → 8 +3 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 7885. A Q 2 K Q 3 2 K Q 6 3 J 7 10 9 5 4 — J 8 5 K 10 9 8 4 2 K 8 A 10 9 6 5 A 10 9 2 6 3 1 NT N → 7 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 8009. A K Q 4 A Q 3 5 2 J 8 7 6 8 10 9 6 2 A K Q J 10 9 6 10 10 9 5 2 K 5 8 3 K 9 4 3 2 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 8295. A K Q 10 A K 3 5 3 J 10 8 2 9 6 5 A K Q J 8 6 2 9 6 4 8 5 4 2 Q 10 9 2 10 9 K 7 3 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 Simulation 8Z15   Main Top   Stayman or Pass?

 8390. A 8 5 K Q 6 5 Q J K 10 7 3 Q 10 10 2 A K 8 6 5 3 2 8 4 K 9 4 2 A 9 3 10 9 J 9 6 2 1 NT N → 42 N → 8 +3 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 8669. K Q 10 2 Q 10 5 A J K 9 6 4 8 5 A K 6 3 Q 5 J 10 7 3 2 A 9 4 9 2 K 10 9 8 6 3 2 8 1 NT N → 42 N → 8 +3 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 8810. 10 4 2 A Q 6 3 A Q 10 K J 10 K Q 9 5 2 8 6 5 3 8 7 3 2 A 8 K 10 9 5 K J 9 2 9 6 4 1 NT N → 7 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 9071. 10 2 A K Q 2 K 6 3 K J 9 2 A K 8 5 4 10 9 9 8 10 7 4 3 Q 9 6 5 3 A Q J 10 5 2 8 6 1 NT N → 42 N → 9 +4 N → 9 J 7 6 3 J 8 7 4 7 4 A Q 5

 9319. K Q 10 5 A K 9 6 Q J J 4 3 A 9 8 4 Q 10 2 9 8 K 10 8 6 2 5 3 A K 10 6 5 3 2 9 7 2 1 NT N → 42 N → 8 +3 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 9388. A K 2 K Q 6 5 2 Q 9 2 K 4 Q 10 9 A 10 9 K 10 10 9 7 6 2 8 5 4 3 A J 8 6 5 3 J 8 3 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 9537. A Q 5 2 K Q 9 5 A J 9 6 4 K 10 8 4 A 6 2 9 6 5 K 10 2 9 10 3 K Q 10 8 3 2 J 8 7 3 1 NT N → 7 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 9551. A K Q K 10 9 6 3 A J 7 6 4 10 4 A Q K 9 8 5 3 K 10 8 2 9 8 5 2 5 2 Q 10 6 2 J 9 3 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 9601. K Q 4 K Q 9 3 A 9 K 9 4 3 A 8 5 2 A 5 2 Q 8 3 8 7 2 10 9 10 6 K J 10 6 5 2 J 10 6 1 NT N → 62 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 9916. A K 10 9 A Q 3 10 9 5 K 9 8 — 9 6 2 Q J 6 3 J 10 7 4 3 2 Q 8 5 4 2 K 10 5 A K 8 2 6 1 NT N → 8 +2 N → 74 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 Simulation 8Z15   Main Top   Stayman or Pass?

 9981. A Q 9 8 A K 2 K 10 8 5 J 6 10 10 6 3 9 3 K 10 9 8 7 4 3 K 5 4 2 Q 9 5 A Q J 6 2 2 1 NT N → 82 N → 9 +4 N → 9 J 7 6 3 J 8 7 4 7 4 A Q 5

 9982. A Q 5 2 A 9 6 K Q 6 3 J 2 K 10 9 4 5 2 J 8 5 10 6 4 3 8 K Q 10 3 A 10 9 2 K 9 8 7 1 NT N → 72 N → 9 +3 N → 9 + J 7 6 3 J 8 7 4 7 4 A Q 5

 9983. A 10 4 K Q 9 6 K Q J 9 8 3 K Q 8 3 A 8 6 5 2 K J 7 6 9 5 2 A 10 5 2 10 9 3 10 4 2 1 NT N → 72 N → 8 +3 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 9984. A Q 10 2 K Q 2 K 9 J 9 6 4 9 8 5 A 9 5 A Q J 10 6 5 7 K 4 10 6 3 8 3 2 K 10 8 3 2 1 NT N → 72 N → 9 +3 N → 9 + J 7 6 3 J 8 7 4 7 4 A Q 5

 9985. 10 9 A 10 9 3 A K J 6 K 8 4 A K Q 5 4 K Q 5 9 5 2 6 2 8 2 6 2 Q 10 8 3 J 10 9 7 3 1 NT N → 82 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 9986. 8 2 A K 9 6 A K 9 K 8 6 3 A K Q 9 5 3 J 10 8 5 3 10 2 10 5 4 Q 10 2 Q 6 2 J 9 7 4 1 NT N → 82 N → 104 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 9987. A K 2 10 9 3 K J K J 10 7 4 10 9 8 5 A K Q 6 5 10 5 9 6 Q 4 2 A Q 9 8 6 3 2 8 3 2 1 NT N → 3 +2 NT N → 32 NT N → 3 J 7 6 3 J 8 7 4 7 4 A Q 5

 9988. K 9 A K 9 K Q J 5 10 8 3 2 Q 10 8 4 Q 2 A 9 8 6 K 7 6 A 5 2 10 6 5 3 10 3 2 J 9 4 1 NT N → 8 +3 NT N → 83 NT N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 9989. A 5 2 A Q 5 2 A 10 5 3 K 6 K Q 10 9 9 9 6 2 10 9 8 4 3 8 4 K 10 6 3 K Q J 8 J 7 2 1 NT N → 82 N → 9 +4 N → 9 J 7 6 3 J 8 7 4 7 4 A Q 5

 9990. Q 10 8 4 A Q 5 3 K Q K 10 3 K 5 — A J 10 9 6 5 2 J 7 6 2 A 9 2 K 10 9 6 2 8 3 9 8 4 1 NT N → 52 N → 8 +3 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 Simulation 8Z15   Main Top   Stayman or Pass?

 9991. A 8 A 10 3 A 10 6 K J 8 7 6 Q 5 K Q 6 5 K 8 3 2 10 9 3 K 10 9 4 2 9 2 Q J 9 5 4 2 1 NT N → 93 NT N → 9 +3 NT N → 9 + J 7 6 3 J 8 7 4 7 4 A Q 5

 9992. A 5 2 A K 10 5 3 2 K J 8 4 10 9 8 4 9 6 2 J 8 6 9 3 2 K Q Q 5 3 A K Q 10 9 10 7 6 1 NT N → 7 +2 NT N → 72 NT N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 9993. K 9 5 K Q 10 9 3 A Q 5 J 2 A 8 4 2 J 10 6 2 K 9 7 6 3 Q 10 2 A 6 5 K 9 8 3 10 8 4 1 NT N → 72 N → 9 +3 N → 9 + J 7 6 3 J 8 7 4 7 4 A Q 5

 9994. A Q 9 A K 3 2 K 6 2 9 6 2 10 2 5 Q J 8 3 K J 10 8 4 3 K 8 5 4 Q 10 9 6 A 10 9 5 7 1 NT N → 7 +2 N → 73 N → 7 J 7 6 3 J 8 7 4 7 4 A Q 5

 9995. A K 4 K 10 9 Q 9 K J 8 3 2 Q 10 9 5 2 5 K 10 8 6 5 2 4 8 A Q 6 3 2 A J 3 10 9 7 6 1 NT N → 5 +2 NT N → 52 NT N → 5 J 7 6 3 J 8 7 4 7 4 A Q 5

 9996. K Q 2 A K 5 K 10 6 5 3 J 4 A 9 5 4 9 3 Q J 9 2 10 3 2 10 8 Q 10 6 2 A 8 K 9 8 7 6 1 NT N → 8 +2 NT N → 8 +2 NT N → 8 + J 7 6 3 J 8 7 4 7 4 A Q 5

 9997. A K K Q 6 2 A J 6 5 10 4 3 Q 8 4 2 — Q 9 8 2 K 9 8 7 6 10 9 5 A 10 9 5 3 K 10 3 J 2 1 NT N → 72 N → 8 +4 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 9998. K Q 10 A K Q 5 Q 9 2 9 8 6 A 5 4 3 2 A K J 6 5 3 J 4 9 8 2 10 9 6 10 8 K 10 7 3 2 1 NT N → 72 N → 10 +3 N → 10 + J 7 6 3 J 8 7 4 7 4 A Q 5

 9999. Q 5 2 K Q 10 9 A J 10 K J 3 K 9 5 3 K Q 8 5 3 2 10 7 2 A 10 8 4 A 6 2 9 6 9 8 6 4 1 NT N → 8 +2 N → 83 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 10000. 9 5 4 A K Q 3 K Q J 8 8 4 Q 2 10 9 A 9 6 2 K 10 7 6 3 A K 10 8 6 5 2 10 5 3 J 9 2 1 NT N → 52 N → 8 +3 N → 8 J 7 6 3 J 8 7 4 7 4 A Q 5

 Simulation 8Z15   Main Top   Stayman or Pass?