Slam bidding. Gerber
Hey partner, a "No Trump" Slam is on! How many Aces have you got?
But be careful . . .
"Gerber" is used in fewer circumstances nowadays! These days, the only time it's used is after No Trumps has been agreed for the contract.
(For all suit situations, it's much safer, reliable, informative and extendable to use Blackwood to ask about the the 4 Aces (or the 5 "key-cards"). What's more, for these suit contracts, nearly all your partners these days are most probably NOT using Gerber in their 'bridge language').
How Gerber works in No Trumps
Anyway, you and your brilliant partner have reached a NT contract at some level, usually 2NT or 3NT, and you think you have the Strength for a NT Slam, typically 33 points, and/or the necessary Shape (e.g. one nice very long suit in one hand with no honour gaps between you; few if any voids or singletons; preferably not a flat hand with 4333 shape).
So you now need to know if you have the 3rd vital ingredient: Controls. In No Trumps, that can only be the necessary Aces, or possibly Kings, that can stop the enemy from winning more than one trick, or, worse still: running away in another suit (that you cannot trump, of course). For example, after this sequence:
2NT - 4
Here, the opener is strong, 20-22HCP, and has limited his hand to that range. But prior to bidding, the responder has an undeclared hand, and for all we know could have enough for a Slam. Only she knows, so she becomes the "captain" and invokes Gerber if she thinks a NT slam could be possible, and wants to know about Aces. In that case she bids 4.
Reply :
- 4
=0 or 4 Aces - 4
=1 Ace - 4
=2 Aces - 4NT=3 Aces
If the answer was not one that the captain wanted to hear, she says "that's enough" by bidding 4NT. On the other hand, if, for example, the answer was a good one, and as a result all 4 Aces are present within the partnership, the Gerber invoker can now think about a Grand Slam, and could choose to ask about partner's Kings by bidding 5. Reply :
- 5=0 or 4 Kings
- 5=1 King
- 5=2 Kings
- 5NT=3 Kings
Other examples of Gerber NT slam-exploring sequences would be:
2NT - 4
1NT - 4
2 - 2NT - 4
1 - 2 - 2NT - 4
What's the problem with Gerber?
When exploring suit-slams, Gerber would confuse the meanings of partners' bids if you also want to use any of the conventions that use the 4-level bids to explore Slam more accurately and more penetratingly.
The 4 "Gerber asking bid" will be confused, for example, with a splinter bid or a cue bid.
So why use Gerber at all, given the benefits of Blackwood?
Blackwood is poor for No Trumps contracts. That's because, after an answer has been given to a 4NT "keycard-asking" bid, a following bid of 5NT has two very different possible interpretations:
- OK, that's good, let's explore Grand Slam; how many kings have you got?
- Oh, we're too weak to even get to Small Slam, let's stop there
. . . so a final contract preference of 5NT would be confused with a Grand Slam enquiry bid asking for Kings! Oh dear. Imagine the conversation after the game.
So if Gerber is to be used to get round this problem, then it's best used in conjunction with Blackwood, as opposed to instead of Blackwood, because of the superiority of Blackwood in exploring suit slams, as mentioned above.
By the way, there actually is one small advantage of Gerber over Blackwood in suit slams. Both the question bids and the answer bids are all made at a lower bid level: 4 is four bids lower than 4NT. In the event that insufficient Aces are present, it therefore more easily allows for escape into a lower and still-makeable final contract than does Blackwood. This small benefit can be advantageous in exploring minor suit slams, but weighs poorly against the many advantages of using Blackwood for suit slams.
Quantitative NT Slam bidding
Make sure you understand the use of "quantitative NT Slam bidding", which is another way that both Gerber and Blackwood are by-passed in NT Slam exploration.
A Gerber Question
Does the 4 clubs rebid in this example below mean a Club re-bid, or is it 'Gerber' asking for Aces ?
1 - 2 - 2NT - 4
Answer: Because of the NT balanced hand re-bid from opener, it's asking for Aces. If you wanted to re-bid clubs, then re-bid at the 3 level.
If you use Quantitative NT Slam bidding then you could ask for 'specific point count' by bidding 4NT.
Now try the quiz
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