This Week in Bridge
(491) The King-Jack Guess
© AiB Robert S. Todd
Level: 5 of 10 (2 of 6) robert@advinbridge.com
General
Many aspects of bridge fundamentally come down to a guess. These are not random or uneducated actions but guesses where we must apply our knowledge to pull the odds into our favor. When the dummy has the King and Jack of a suit and we lead up to that suit, we have a guess to make: should we play the Jack, or should we play the King? This situation (and many of its variants) come up frequently and here we look at it in more detail to help us improve our “guessing.”
Layout Possibilities
Before we go into detail about how to play (and why) when we lead up to the King-Jack, let’s look at this situation in more detail so we can better understand the possible layout of the cards around the table.
Example 1
KJx
xxx
If this is our situation, then there are four possible layouts of the opponents’ honors (Ace & Queen) that affect our trick-taking abilities. We will look at what happens when we lead up to both of dummy’s honors (working our way up, first leading to the Jack and later to the King).
1. Ace & Queen both onside (with LHO) – We can win two tricks if we lead up to the Jack, return to our hand, and later lead up to the King.
2. Ace & Queen both offside (with RHO) – We cannot get any tricks from dummy’s honors (King or Jack), as each of them will be captured by the honor sitting over them (the Jack by the Queen and the King by the Ace).
3. Queen onside (with LHO) & Ace offside (with RHO) – When we first lead up to the Jack, it will force RHO’s Ace and develop our King into a winner.
4. Ace onside (with LHO) & Queen offside (with RHO) – If we lead up to the Jack, it will lose to the Queen. Later we can lead up towards the King, which will eventually be developed into a winner with the Ace onside.
In this scenario we see that in order to ensure we take all the tricks we are entitled to (two tricks if both the Ace and Queen are onside) we need to lead up to both honors, starting with the Jack then later the King.
Length of Declarer’s Holding
When we have both the King and Jack with some small cards in the dummy (at least KJx) but have fewer cards in our hand (one or two) then we have a guess of which card to play from the dummy. If we have more length in our hand we usually lead up to the Jack, hoping that the layout is #1 above, and we can produce two tricks. Our choice of play is affected by the number of cards we have in our hand and whether a discard would be useful for us in reducing our losers in other suits. We will focus our discussion here on suit contracts, since we are less likely to play this suit in a notrump contract when we have shortness.
Singleton
If we have a singleton in our hand and lead up towards the KJx+ then we have to decide whether to play the King or the Jack. Playing the King (if LHO has ducked their Ace) will result in a winner and no losers in this suit. In a suit contract this is excellent! If we lead up to the Jack and it forces RHO to play the Ace, we set up a discard on the King. Which play we should make is a guess, but if a discard from another suit will not help us, then we should lead up to the King, hoping to “steal a trick.”
Doubleton
When we have a doubleton in our hand and KJx+ in the dummy, then our primary goal is to lose only one trick in this suit – to the Ace. The layouts that we need to focus on are #3 and #4 above. If the Queen is onside and not the Ace (case #3) then we need to lead up to the Jack. If the Ace is onside and not the Queen (case #4) then we need to lead up to the King. In order to make this decision more than just a 50% guess, we need to use all of the information available to us from the auction and the play. We will discuss some of these details that help us making a play better than a 50/50 guess below.
Length of Dummy’s Holding
Just as the number of cards in our hand affects our play, the number of cards in the dummy may affect our choice of plays as well. When the Ace is onside there is a chance that our LHO will take a look at the KJx+ in the dummy and choose to take their Ace immediately - fearing that they will “lose their Ace” if we have a singleton. This play takes us off our King-Jack guess. Thus, if our LHO plays low, there is a slightly greater chance that they do not have the Ace (that our RHO has the Ace). Without any other information the best play to produce one winner is to play up to the Jack.
The more cards there are in the dummy, the more likely it is that our LHO will choose to take their Ace – thus the more likely it is that they do not hold it if they do not take it.
Example 2
KJxxx
If we lead up to the dummy with this holding and LHO has the Ace, they will be worried that we have a singleton and be more likely to take their Ace, not wanting us to steal a trick by playing the King. If dummy was shorter (KJxx or KJx), they would be less worried about us having a singleton and be more likely to duck their Ace, giving us a chance to misguess. The longer the suit in the dummy, the more likely LHO is to be afraid to duck their Ace and more likely they are to play second hand high.
Note: One way to use this tendency against LHO is to lead up towards KJxxx (or longer) early in the play when we have a doubleton. Our LHO will be convinced that we have a singleton (they will not yet have a count on the hand) and will be extremely likely to play the Ace if they have it. Knowing this, we should be able to better guess how best to play in this situation (to play the Jack).
Counting High Card Points
One reason that we may wish to wait until later in the hand to play a suit where we have a King-Jack guess is to locate (or count) the HCP in all the other suits. Knowing the location of the other HCP may help us better determine the layout of the suit we are trying to guess. For example, if we discover that our RHO has 8-9 HCP in the other suits and they did not bid in the auction (assuming they had a chance to do so at a reasonable level) then it is extremely unlikely that they also have the Ace of this suit. We can safely lead up to the King, expecting our LHO to have the missing Ace. In many situations, the longer we wait to attempt to “guess,” the more information we can gather about the opponents’ hands (especially their HCP in this situation) and the more likely we are to guess the situation correctly.
Conclusion
Leading up to towards a suit that has the King-Jack tenace (especially when it is in the dummy) is another one of these situations in bridge where you must make a guess. But this is not necessarily a random guess (only a 50% chance), it can be an educated one. There is a saying in bridge that expert players’ finesses work about 75% of the time. Surprisingly, this often turns out to be true. You can make your guess much better than 50% because there is a lot of useful information and techniques available to help you do a better job than just a random guess. You should work hard to use all of the techniques and skills (like information gathering) to do much better than just 50% in this guess situation.