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How to read your opponents’ cards

#1 User is offline   mikeh 

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Posted 2021-July-01, 22:37

The opening lead is a small club. You duck, losing to the King, and the club return is ruffed. East now plays the spade Ace and switches to a diamond



This isn’t exactly a tough hand but I thought it interesting because it shows how much information is often available.

Presented as a problem, I expect most intermediates or better would work this out. The secret to becoming a good player is to pay attention on every hand, such that (over time) this sort of thinking becomes second nature.


Opener would not cash the spade Ace and play a diamond if he had Axx in spades to begin with: if he was going passive, he’d exit his last spade and if he was hoping for another ruff or to retain control he’d not cash the spade.

More importantly, he’d never lead a diamond if he had a heart sequence, nor would he cash the spade Ace. He’d drive out the heart Ace while he still had control in spades.

He’s marked with the diamond King for his opening bid, and he can’t hold KQxxx(x) in hearts because he’d switch to the heart King rather than cash his spade Ace.

So we can infer that he held either Ax KJxxxx Kxxx x or Ax KJxxx Kxxxx x

So where does that leave us? We’ve lost two tricks already.

We have 2 club winners, 2 diamond winners and one heart. So we need 5 trump tricks, but west has 8x in spades sitting over dummy’s Q7. We need to ruff one heart with the 7 and another with the Queen….those two ruffs will, combined with our KJ10, give us 5 trump tricks.

This means that we need west to hold Qx in hearts.

Win the diamond in hand. We can afford to cash one spade just in case east fooled us and did start with Axx. He shows out, as expected.

Cash the club Ace and then this being the critical play, unblock the heart Ace. Cash diamond Ace, ruff a diamond, and take a heart pitch on the good club Queen. Now ruff a heart with the 7 and score 3 more tricks by way of a high cross-ruff.

Note that if you don’t unblock the heart Ace, but instead ruff a diamond to hand…then pitch a heart on the club and cross to the now stiff heart Ace, when you ruff dummy’s last diamond, west pitches his Herat Queen and down you go.

I thought this was a good hand. If you’ve ever wondered how experts seem to play double-dummy, it’s often based on this kind of inferential reading. This hand was one of the easier ones…..we have basically a complete read of the opponents’ hands at trick 4.

Yes, they should have beaten us by switching to a heart rather than cashing the spade Ace, but defenders often make errors and it’s declarer’s job to make them pay when they do.
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#2 User is offline   LBengtsson 

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Posted 2021-July-02, 03:40

View Postmikeh, on 2021-July-01, 22:37, said:

Yes, they should have beaten us by switching to a heart rather than cashing the spade Ace, but defenders often make errors and it’s declarer’s job to make them pay when they do.


yes, defense was not correct but this is a excellent hand to show card reading. thanks for posting, mike.
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#3 User is online   Cyberyeti 

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Posted 2021-July-02, 03:55

You could avoid any entry issue by unblocking A on the ruff, but that would give away the club holding for certain (you are known to hold the Q, but might not have J or 10) and might make the heart switch more attractive.

Also if the lead was 3 you might consider flying A at trick 1, more difficult if it's higher.
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#4 User is offline   AL78 

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Posted 2021-July-02, 06:19

I agree that is a nice instructive hand showing how to infer the layout and plan the play accordingly. What makes it easy to do the former is the fact that one opponent opened the bidding, your side ended up in game on a combined 24 count, and the partner of the opening bidder showed up with the K at trick one. The meaning of the absence of a heart switch is something I might miss myself if I was tired, but it comes down to what a competant defender would most likely play if they held a heart honor sequence.

"So where does that leave us? We’ve lost two tricks already."

At that stage, you've lost three tricks, K, ruff, and A, doesn't affect the rest of the analysis though.
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#5 User is offline   Winstonm 

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Posted 2021-July-02, 11:10

Another minor inference that the hearts are likely 5-2 is that after winning the club opponent did not switch to a singleton heart trying to get a crossruff going.
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#6 User is offline   jillybean 

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Posted 2021-July-02, 12:40

Very useful, instructive post thank you. Now if I can force myself to stop and pay attention on every hand, this may eventually become second nature.
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