In Their Own Words

Blackwood on Blackwood

by Easley Blackwood

The following rubber bridge hand resulted in the birth of Blackwood:

♠ K Q 6 2
K Q J 8 3
♣ 6
♠A J 10 8 7 4
9 2
A 7
♣ K Q 5
North South
3 3♠
4♠ 6♠

The defenders had no difficulty in cashing their two aces and North-South were at each other’s throats. North reflected in no uncertain terms upon South’s ability; South pointed out that North could easily have held AQxxx in hearts in which case the slam was cold.

North-South were using the Culbertson 4-5 notrump convention. As the Culbertson bid of 4NT guaranteed either two aces and the king of a bid suit or three aces, South was precluded from using it. Instead, he gambled and lost.

I felt that it was asking too much for the 4NT bid to be both an asking and a telling bid. Why not let this bid ask a question and let it go at that? Let the question be, specifically, “Partner, how many aces do you have?” The responses would be simple:

5 0 or 4 aces
5 1 ace
5 2 aces
5 3 aces

The fact that the 5♣ response shows either no ace of all four should not bother you. It always is possible to distinguish which – if partner responds 5♣ and you have even one ace in your hand, he must have none. If you have no aces, he should have four. If you are investigating slam off all four aces, perhaps your bidding system needs an overhaul.

After a Blackwood 4NT and an ace-showing response, a bid of 5NT guarantees that your side holds all the aces and asks partner to show his kings in steps similar to the responses over 4NT.

The Blackwood 4NT bid starts a captain and mate relationship. Your duty as responder is to tell partner how many aces you hold, and if partner then decides to play at the five level, you need an exceptional reason to doubt his word and go on. Similarly, if partner bids a slam, that is where the hand should be played.

However, once partner bids 5NT, confirming possession of all four aces and showing an interest in a grand slam, you come into your own. No longer need you meekly respond with the number of kings you hold – you may exercise judgment. A solid suit of your won that will provide discards or a singleton in an unbid suit may be all that partner needs to make a grand slam, even if one or more kings is missing, and you may jump straight to the grand slam. Caution – danger!

The first thing to learn about the Blackwood Convention is that it is not suitable for all hands in the slam zone. Possession of a combined point count of at least 33 does not guarantee that a slam can be made. You cannot be missing two aces, but there is the possibility that you are missing the ace and king of the same suit, and the opponents can cash two quick tricks in that suit. The Blackwood Convention will not uncover this fact. Consider this hand:

♠K Q J 7 6 4   K Q 10   7 6   ♣A Q

You open the bidding with 1 and partner makes a forcing raise to 3. It is obvious that if partner holds the right cards, you should be able to make a slam, so you bid a Blackwood 4NT. Partner dutifully responds 5, showing two aces. Whiter now? Partner could hold either of these two hands:

a. ♠A 10 5 3   A J 2   8 4   ♣K J 3 2

b. ♠A 10 5 3   4 2   A J 4  ♣K J 3 2

The point count and distribution pattern of the two hands are exactly the same. However, opposite hand (a) there are two quick losers; with hand (b) 12 tricks are there for the taking.

Thus we have discovered the first cardinal rule for not applying Blackwood: Do not use Blackwood with a worthless doubleton in an unbid suit.

An extension of the above principle brings us to the second cardinal rule: Do not use Blackwood with a void. Unless partner’s response confirms that your side holds all of the aces, you will not know whether one of his aces is in your void suit. If it is, you might have too many losers in one of your side suits.

In summary: If partner’s response to your 4NT inquiry for aces will not tell you whether or not to bid a slam, DO NOT employ Blackwood.

About Easley Blackwood

When the late Easley Blackwood first thought of the convention* that bears his name, he was a rising star in the insurance world. He submitted the original article to “The Bridge World” magazine in 1934 under the nom-de-plume Earnest Wormwood, as he was not eager for publicity. It was returned by the late Albert Morehead with a polite note that the Wormwood Convention would never become popular! Morehead was rarely wrong in these matters, but this time.

The Blackwood Convention has become the most universally used convention in contract bridge. As a natural corollary, it also has become the most misused. Many players tend to overlook the fact that the Blackwood Convention was designed as much to stay out of unmakable slams as to get to slams where the only information needed is the number of aces held by the partnership.

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