Artificial Intelligence?

Artificial intelligence has come a long way… not! I asked Google’s self-proclaimed AI Genius:

How do you play A-J-10-9-8 opposite 5-4-3-2 at bridge?

Any experienced bridge player knows the best play for four tricks is to take two finesses. This is 76 percent (a priori) whereas cashing the ace first is under 66 percent. Now put on your heaviest boots, stand back, and read what the AI Genius had to say (quoted verbatim).

“Okay, let’s break down how to play the suit combination A-J-10-9-8 opposite 5-4-3-2. You have 9 cards in the suit, missing the King (K) and Queen (Q). Your goal is to maximize the number of tricks you win from this suit. There are four missing cards total: K, Q, 7, 6. The location of the K and Q is crucial.

“The Standard and Recommended Play: Cash the Ace First. Start by playing the Ace from the A-J-10-9-8 hand. Watch carefully what the opponents play.

• If K or Q drops (singleton): Excellent! The opponent had only one of the key honors. Now, lead the Jack (or 10, 9, 8 - they are equivalent winners). All your remaining J-10-9-8 cards are high. You will win 5 tricks (Ace + J + 10 + 9 + 8). This happens about 20% of the time (roughly 10% for K singleton, 10% for Q singleton).
• If both K and Q drop (doubleton): Even better! The opponent had exactly K-Q. All your remaining J-10-9-8 cards are high. You will win 5 tricks. This happens about 4% of the time.
• If neither K nor Q drops: This is the most likely scenario (around 76% of the time). One or both opponents still hold the K and Q among their remaining cards.

“If Neither K nor Q Dropped: Your next step is to take a finesse. You need to lead from the hand opposite the honors (the 5-4-3-2 hand). Assuming you can get back to that hand (you have an entry), lead a low card (e.g., the 2). Let’s say the opponent on your Left (LHO) plays low. Now, from the J-10-9-8 hand (where the Ace was), play the Jack. This is the finesse.

• If the Jack wins: Congratulations, the finesse succeeded! This means the opponent on your Right (RHO) holds the K and/or Q (specifically, RHO must have started with K-Q-x or K-Q-x-x). You have won the Ace and the Jack. You will lose tricks to the King and Queen later. To maximize, if you have another entry to the 5-4-3-2 hand, you can lead low towards your 10-9-8 later to take a second finesse for the 10. In this successful finesse scenario, you will typically make 3 tricks (Ace, Jack, and the 10 via a second finesse).
• If the Jack loses (to the K or Q): The finesse failed. This means the opponent on your Left (LHO) started with the King, the Queen, or both. Although you lost the Jack, the good news is that your remaining 10-9-8 are now established as winners (because the Ace took care of one high honor possibility, and the losing finesse took care of the other). You will make the Ace, plus the 10, 9, and 8. In this failed finesse scenario, you will make 4 tricks (Ace, 10, 9, 8).

“Why is cashing the ace first generally better?

• Picks up singletons/doubletons: It’s the only play that guarantees you capture a singleton K, singleton Q, or doubleton K-Q from one opponent, turning those situations into 5 tricks instead of potentially losing a trick unnecessarily.
• High Success Rate for 4+ Tricks: You get 5 tricks if K/Q singleton or K-Q doubleton (~24% chance). You get 4 tricks if the subsequent finesse fails (~76% * ~50% = ~38% chance, assuming K/Q split 50/50 when finesse is taken). Combining these gives a very high chance of making at least 4 tricks.
• Safety: It guarantees one trick immediately.

“Alternative Play (Usually Inferior): Finesse First. You could lead low from the 5-4-3-2 hand immediately and finesse the Jack.

• If Finesse Wins (RHO has K-Q): You win the Jack. You then cash the Ace. You will lose to the K and Q later. You make 3 tricks (Jack, Ace, and 10 via second finesse if possible).
• If Finesse Loses (LHO has K or Q or K-Q): You lose the Jack. You cash the Ace later (possibly dropping the other honor if LHO had K-Q or they were split). Your 10-9-8 become winners. You make 4 tricks (Ace, 10, 9, 8).

“Comparing the two, cashing the Ace first gains whenever an opponent has a singleton K, singleton Q, or doubleton K-Q, turning those into 5 tricks instead of 4 (if K/Q singleton) or 3 (if K-Q doubleton with RHO and you finesse first). In all other cases, the number of tricks is the same. Therefore, playing the Ace first has a slightly higher trick expectation.

Summary Table (Playing Ace First)

K-Q Distribution	Play Sequence	Tricks Won	Approx. Probability
K singleton (either opp)	Ace (K drops), then J	5	20%
Q singleton (either opp)	Ace (Q drops), then J	5	20%
K-Q doubleton (either opp)	Ace (K-Q drop), then J	5	4%
K-Q with RHO (longer)	Ace (no drop), low to J (wins)	3	24%
K-Q with LHO (longer)	Ace (no drop), low to J (loses)	4	24%
K/Q split (longer)	Ace (no drop), low to J (loses)	4	52%

“Key Takeaway: Unless you have specific reasons based on bidding or card play (like needing to keep a particular opponent off lead, or a severe lack of entries), cash the Ace first. Then, if no honor drops, lead low towards your J-10-9-8 and finesse the Jack.”

As I see it, the “key takeaway” is to take away their keys forever, though I must admit being jealous of winning five tricks. -RP

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© 2025 Richard Pavlicek