This Week in Bridge
(424) Bidding the 4th Suit in 2/1 GF Auctions
© AiB Robert S. Todd
Level: 7 of 10 (3 of 6) robert@advinbridge.com
General
In a 2/1 Game Forcing auction, we usually get to make natural bids because all our bids are forcing, but there are times when we do not have enough length to make another natural bid and we do not hold the right stoppers to make it a good idea to rebid NT. This is when we use a bid of the 4th suit. When we bid the 4th suit, we usually are doing so because we are not sure of what to do (whether in a 2/1 GF auction or not.) 4th suit bids in 2/1 GF auctions make for relatively complex auctions. We will look at these in detail with an effort to understand what partner has when they bid the 4th suit.
Note: For most of the discussion we will be looking at cases when Responder bids the 4th suit on their second call. Later we will examine even more complex auctions where the 4th suit bid happens later in the auction.
When Responder Will NOT Bid 4th Suit (Negative Inferences)
Before we look at the 4th suit auctions in detail (to examine what partner has when they bid the 4th suit) let’s think about what partner does not have when they bid 4th suit – because we know they have a better bid for these hands.
We will assume that the auction begins in a common 2/1 GF way:
1X 2Y
2Z
This 3rd suit bid (2Z) could be at the 3-level (3Z).
Example 1
1♠ 2♣
2♥
Here are some hands where partner will know what to do and therefore NOT bid the 4th suit:
Fit for Opener’s primary suit (e.g., 3c♠ support.) With this hand Responder would show the fit on their second call.
Fit for Opener’s secondary suit (e.g., 4c♥ support.) With this hand Responder would raise Opener’s second suit.
Balanced hand with a stopper in the 4th suit (i.e. stopper in ♦). In this case, Responder will rebid notrump.
A long suit (6+cards) of their own. In this case Responder will rebid their suit.
Now that we have ruled out some of the basic hand types from the Responder for 4th suit rebid we can move on to examining what Responder might have when they do bid the 4th suit.
12 Auctions
There are 12 basic 2/1 Game Forcing auctions where Responder’s second bid can be the 4th suit. We will look at each of these auctions in detail. This may seem somewhat tedious, but the point of this is to help us understand what partner might have. Before we go into the details, let us take a moment to summarize and give you a preview of the results we’ll see.
When partner bids the 4th suit they will generally have one of two hand types:
A relatively flat (non-distributional) hand without a stopper in the 4th suit.
A 2-suited hand (5-5+ or 5-6+ based on the order of the suits bid) that is inappropriate for bidding notrump on their second call.
Our challenge will be to determine which of these hands is most common and how to use partner’s subsequent bidding to determine which of these hands partner has. We will look at the possible hand shapes responder can have for each of these auctions and discuss which shapes will be easy to handle after we bid the 4th suit and which shapes (hands) can be handled better by choosing a different call.
4th Suit Forcing in 2/1 GF Auctions
1. 1♠ 2♣
2♦ 2♥
(No stoppers, less shapely) 2-3-3-5, 2-4-3-4, 2-4-2-5, 1-4-3-5
2. 1♠ 2♣
2♥ 3♦
(Shapely hands) 5♦ - 6♣ OR (No stoppers, less shapely) 2-2-4-5, 2-3-3-5, 2-3-4-4, 1-3-4-5
3. 1♠ 2♦
2♥ 3♣
(Shapely hands) 6♦ - 5+♣ OR (No stoppers, less shapely) 2-3-5-3, 2-2-5-4, 1-3-5-4, 2/1-5-5, 0-3-5-5
4. 1♠ 2♦
3♣ 3♥
(Shapely hands) 6+♦ - 5♥ OR (No stoppers, less shapely) 2-3-5-3, 2-4-4-3, 2-4-5-2, 2-2-5-4, 1-2-5-5, 2-1-5-5, 0-3-5-5, 1-3-5-4.
5. 1♠ 2♥
3♣ 3♦
(Shapely hands) 6♥+ - 5♦+ OR (No stoppers, less shapely) 2-3-3-5, 2-5-3-3, 2-5-4-2, 2-5-5-1, 1-5-5-2,
0-5-5-3
6. 1♠ 2♥
3♦ 4♣
(Shapely hands) 6♥+ - 5♣+ OR No stopper since beyond 3NT. Advanced Cuebids with ♦ fit.
7. 1♥ 2♣
2♦ 2♠
(Shapely hands) 6♣+ - 5♠+ OR (No stoppers, less shapely) 4-2-3-4, 3-2-3-5, 4-2-2-5, 4-1-3-5
8. 1♥ 2♣
2♠ 3♦
(Shapely hands) 6♣+ - 5♦ OR (No stoppers, less shapely) 3-2-3-5, 2-2-4-5, 3-1-4-5, 3-2-4-4
9. 1♥ 2♦
2♠ 3♣
(Shapely hands) 6+♦ - 5+♣ OR (No stoppers, less shapely) 3-2-5-3, 2-2-5-4, 3-1-5-4, 2-1-5-5, 1-2-5-5, 3-0-5-5
10. 1♥ 2♦
3♣ 3♠
(Shapely hands) 6+♦ - 5♠ OR (No stoppers, less shapely) 4-2-4-3, 2-2-5-4, 1-2-5-5, 2-1-5-5, 3-1-5-4,
3-0-5-5
11. 1♦ 2♣
2♥ 2♠
(Shapely hands) 6+♣ - 5+♠ OR (Unlikely, better to bid 1♠ first), (No stoppers, less shapely), Opener has only 4-card ♦, ♥ stopper, not ♠ stopper. So, 2♠ shows half a ♠ stopper.
12. 1♦ 2♣
2♠ 3♥
(Shapely hands) 6+♣ - 5+♥ OR (Unlikely, better to bid 1♥ first), (No stoppers, less shapely), Opener has only 4-card ♦, ♠ stopper, not ♥ stopper. So, 3♥ shows half a ♥ stopper.
Later 4th Suit Bids
If the 4th suit is bid later in the auction (on a 5th or 6th call) then this is a more traditional bid – asking for a stopper. At this point in the auction both players have shown most of their shape naturally, so the main reason left to bid the 4th suit is to ask for a stopper.
Conclusion
As is clear from all the complexity above, these 4th suit bids in 2/1 Game Forcing auctions are not simple. We can see partner can have several difficult hand types for which they will need to use the 4th suit, so we will not always know their exact shape. What we do know is how to bid after the 4th suit. We treat it as partner asking us for a stopper. We bid notrump with a stopper and find the best natural bid without a stopper. If partner bids on over our notrump bid, then they reveal a more shapely hand. But in most cases, it will not be until dummy hits that we actually know why partner bid the 4th suit.