Double Club System

Auctions starting 1H/S

Note: The responses to a 1H/S opening bid in 1st or 2nd position, which are described on this page, are significantly different to the responses to a 1H/S opening bid in 3rd or 4th position (after partner has passed).

What has been shown?

The 1H/S opening bids show an unbalanced hand with no suit longer than the bid major suit. In 1st/2nd position we never open a balanced hand with 1H/S, even if it does have a 5-card major.

Kaplan Interchange

The Double Club System uses the Kaplan Interchange following a 1st/2nd position opening bid of 1H. This is essentially a swap of the 1S and 1NT responses. There are many benefits and no drawbacks to this. One of the greatest benefits is that, in the Double Club System (where a 1H opening bid is always unbalanced) opener never needs to manufacture a rebid in a short minor suit (which is the case in other two-over-one systems).

You and your partner can agree not to play the Kaplan Interchange, in which case a 1NT response to 1H means the same as a 1NT response to 1S, and a 1S response to 1H is natural. But you will be doing yourself a disservice. When opener has a 4=5=2=2 shape and gets a forcing 1NT response, he will be forced to rebid either his doubleton club suit or his 5-card hearts, neither of which is at all desirable.

Strategy

Responder has 4-card or longer support

Responder will raise immediately: to 2H/S with 9 losers, pre-emptively to 3H/S or 4H/S if weak, make a splinter raise if strong and unbalanced, or make a conventional raise to 2NT or 3NT if strong and balanced.

Responder has 3-card support

Responder will raise to 2H/S with 9 losers (unless he is 4-3-3-3, when 1NT is preferred). With 8 losers, responder should start with a forcing 1NT and jump support opener's suit on the next round.

With 7 losers or fewer, responder should first bid a new suit naturally, and is allowed to bid at the two level to do so even if having less than than 12 hcp.

Responder does not have support

Responder bids 1NT (over 1H) with a 5-card or longer spade suit. Otherwise, with 6-12 hcp, he makes the cheapest bid as a forcing relay: 1S (over 1H) or 1NT (over 1S). With 13+ hcp responder can bid a natural new suit at the two level.

Note that the "unbiddable" hand over a 1S opening, the 3=4=3=3 responding hand with 13+ hcp and a 4-card heart suit, will probably do better to respond 1NT rather than manufacturing a bid in a 3-card minor. Responder will be able to jump raise opener's suit on the next round, or bid game in no trumps or opener's suit. Since the 1NT response is forcing this carries no risk of a premature pass. Responder's two-over-one new suit should generally be a 5-card or longer suit unless having 4-card support for opener.

Continuations

1S [Alert] (over 1H)
Artificial and forcing: Denies a 5-card or longer spade suit (although responder may have a 4-card spade suit). If opener then rebids 1NT he shows a 4-card spade suit in a hand too weak to reverse, and responder can pass if he wishes (responder would correct to 2S with a 4-card spade suit).
1NT [Alert] (over 1H)
Artificial and forcing: Shows a 5-card or longer spade suit with no upper limit of strength. Opener next makes his natural rebid, bidding spades at the appropriate level if he has 3-card or longer support.
1NT [Alert] (over 1S)
Forcing: nominally 6-11 hcp but may be stronger when balanced with 3-card support. Denies a 4-card or longer major which could have been bid at the one level. Note that all 3-card raises of opener's suit that have 8 losers or fewer should start with a forcing 1NT and then jump support opener's suit on the next round.
2C/D [Alert]
Natural and game-forcing: nominally a 5-card or longer suit and 12+ hcp, except that the strength requirement can be relaxed when responder has 3-card support for opener and an unbalanced hand with 7 losers or fewer. Note that you should use the forcing 1NT instead if you have 12+ hcp without a 5-card suit, since you will have some degree of support for opener's suit and can jump to game on the next round.
2H (over 1S) [Alert]
Natural and game-forcing: 12+ hcp with a 5-card or longer heart suit.
2H/S
A 9 loser raise with 3-card or longer support. We are happy to make this raise with 9 losers and 4-card support, even though we will later take the push if the opponents protect. They may not protect, so why risk going too high? And, if they do, their bidding gives us information about their holdings.
2S (over 1H)
Natural and game-forcing, 16+ hcp. The System requires that a game-forcing jump takeout response conforms to the Proper Use of the Game-Forcing Jump Takeout.
2NT [Alert]
A conventional 4-card or longer limit raise, showing either exactly 8 losers or a strong hand with 6 losers or better. Responder's hand may contain a singleton or void, since with this number of losers it will either be too strong to splinter or too weak to splinter. Opener assumes that responder has the weaker hand. If opener signs off, responder makes a further try with the stronger hand.
three-level new suit (below 3H/S) [Alert]
Natural and non-forcing: 10-12 hcp with a good 6-card suit.
3H/S
A 4-card pre-emptive raise, showing some shape but more than 9 losers.
3NT [Alert]
A conventional 4-card or longer limit raise, showing 7 losers.
higher-level new suit (above 3H/S)
Splinter. A slam try showing shortage in the bid suit and good support for opener's major suit. Since the partnership is committed to game, a full splinter is a slam try and shows 6 losers or fewer. Opener should sign off in 4H/S with an ill-fitting hand. Otherwise he cue bids controls (and can do so even if he has opened light if the hands appear to fit well).
4H/S
A 5-card pre-emptive raise, showing little in the way of high card strength. It absolutely denies any ace or king, since if opener has good values an ace or king that fits with opener's suits may provide enough help to make a slam. A singleton or void is perfectly all right, however, since although a shortage may be a useful control it will not bolster opener's suit holdings.

Author: Chris Burton
Gravesend Bridge Club