Blackwood

Don't bid a slam with two missing aces

The purpose of the Blackwood convention is to avoid bidding silly slams, such as ones where an opponent can quickly cash two winning aces before you even have a chance to register twelve tricks.

But before you use Blackwood, you need to pay attention to the following...

Don't bid a slam if you cannot win twelve tricks

Blackwood will tell you if you have too many quick losers. It cannot tell you that you have enough winners. Before using Blackwood you should already have ascertained that your partnership's combined strength is likely to produce at least twelve winning tricks. If your only worry is that the defenders might win two tricks before you can win your twelve, then Blackwood will be able to give you the answer.

Don't use Blackwood if you cannot be sure that you can win twelve tricks. Settle for a safe game contract, and a score in your column.

Using Blackwood to count Aces

The Blackwood convention is an artificial bid of 4NT by an unlimited hand. A bid of 4NT is not Blackwood if it is an invitational raise of a natural NT bid by partner, nor if it is made by a limited hand (eg one which has signed off in 3NT on the previous round).

The responses to Blackwood are simple. Responder counts the number of aces he has and replies in steps:

5

0 aces (or all 4 aces).

5

1 ace.

5

2 aces.

5

3 aces.

Using Blackwood to count Kings

If the Blackwood bidder has found that all aces are held, and if he believes that his side will have thirteen winning tricks if all the kings are held as well, he can make a further bid of 5NT to find out the king situation. Responder replies in exactly the same way:

6

0 kings.

6

1 king.

6

2 kings.

6

3 kings.

Signing off as the Blackwood Bidder

When the Blackwood bidder has found that two aces are missing, he will want to sign off at the five level. He can pass responder's last bid, if that is where he wants to play, or bid five of any suit previously shown by the partnership to play there. If he wants to play in 5NT, he cannot bid 5NT as partner will think he is asking for kings! To play in 5NT, he bids a suit not previously shown by the partnership. This is a conventional request for partner to bid 5NT, which will be passed.

If the Blackwood bidder has found that one ace is missing, or if he has found that no ace is missing but he only expects to make twelve winners, he simply bids six of whatever denomination he thinks is best.

If there is no ace missing and he has grand slam ambitions, he may be able to bid seven of something straight away. But if he needs to check on the number of kings he continues with 5NT. Whatever he bids next, following responder's reply, is a sign-off.

When is 4NT not Blackwood?

There are two cases where 4NT is natural:

1. If the 4NT bidder had a natural 3NT bid available, then his bid of 4NT is natural and shows a hand too strong to have bid 3NT, i.e. with values to invite a slam. So 1NT, 2♣; 2♥, 4NT is natural and non-forcing, inviting opener to bid 6NT if maximum or 6♠ with a 4-card spade suit.
2. If the 4NT bidder has previously made any natural NT bid, then his bid of 4NT is a natural sign-off. So 1♠, 3♥; 3NT, 4♣; 4NT is a sign-off. Responder has shown a strong two-suiter in hearts and clubs, but opener has a misfit and minimum values. He has already offered to play in 3NT and now he wants to play in 4NT.

Notes:

1. You cannot use Blackwood after the bidding has started 1NT, 2♣; 2♥ and you have slam-invitational values. If you want to invite or bid slam in hearts, for example, you have to bid 5♥ or 6♥ yourself. Many players have a conventional agreement that a bid of three of the other major after a positive response to Stayman agrees the opener's major and allows a subsequent bid of 4NT by responder to be interpreted as Blackwood, but don't try this unless you know your partner shares this understanding.
2. After the bidding has started 1♠, 3♥; 3NT, 4♣, if opener has club support and slam interest he bids 4♦ as an advance cue bid, so that his partner can bid 4NT as Blackwood if he wishes to.

Author: Chris Burton
Gravesend Bridge Club