Double Club System

Auctions starting 1C, 1D

What has been shown?

Opener has shown either a normal strength unbalanced hand with no suit longer than clubs or a balanced hand with 17+ hcp, or a Game-Forcing hand with clubs as the longest suit, or a Game-Forcing Three-Suited Hand with shortage in any suit other than clubs.

Responder is unlimited at this stage, though he could have nothing. If he has some values, he may have 6-11 hcp with a 4-card major (but no 5-card major), or he may have a strong hand (12+ hcp) with diamonds as the longest suit.

Opener's Continuations

1♥ [Alert]
Forcing. Either natural or a Kokish Relay, after which opener possibly intends to show a strong balanced hand or a strong three-suiter short in diamonds or spades. Responder should usually bid 1S, completing the Kokish Relay, to find out which. If opener follows with 1NT or 2NT then both his 1C and 1H bids are artificial and he has 20-22 hcp or 29+ hcp balanced. If opener follows with any other bid then both his 1C and 1H bids are natural and so is his third bid (responder's two bids remain artificial, however, and do not count as bid suits). You may wish to view the Examples of the Kokish Relay to see how it should be used.
1♠
Shows a 4-card spade suit in addition to a 5-card club suit (unless 4=4=1=4). Any strength, non-forcing.
Note: When opener has a 4=4=1=4 shape with normal opening bid strength then he should open 1C and rebid 1S, to avoid going through the Kokish Relay. Responder can show a heart suit by bidding 1NT next, so a heart fit will not be missed unless responder is very weak.
1NT
A balanced hand of 17-19 hcp, and the club suit may be as short as a doubleton. The System's 1NT Response System is on, exactly as after a 1NT opening bid.
Note: Balanced hands of this strength, even with a 5-card major, must be opened with 1C.
2♣
A single-suited club hand of weak to moderate opening bid strength, about 11-16 hcp. May possibly have a shorter diamond suit but will not have a 4-card major (opener would have bid the major if he had one). Responder should bid 2D if he has a strong hand with diamonds, pass with any hand of 0-9 hcp, and make an invitational bid of 2H or 2S (showing a stopper) or 2NT (showing both majors stopped) with 10-11 hcp. If opener has minimum values, he can reject the try by rebidding 2NT or 3C.
2♦ [Alert]
Artificial and strong, promising a genuine club suit (but not necessarily a diamond suit), and showing a hand too strong to have rebid 3C. Opener has either a Game-Forcing club single-suiter, a Game-Forcing club-diamond reverse (5+ clubs and exactly 4 diamonds), or a Game-Forcing Three-Suited Hand with short hearts. Responder should usually relay with 2H to allow opener to show which hand type he has.
2♥
Natural and Game-Forcing, showing a hand with a good quality 5-card or longer club suit and a good quality 4-card heart suit.
2♠
Natural and Game-Forcing, showing a hand with a good quality 5-card or longer club suit and a good quality 4-card spade suit.
2NT
A very strong balanced hand of 27-28 hcp, and the club suit may be as short as a doubleton. The System's 2NT Response System is on.
3♣
Natural and game-invitational, showing a hand with a good quality 6-card or longer club suit and approximately 17-18 hcp, with no 4-card or longer major suit.
higher bids
Not defined.

Author: Chris Burton
Gravesend Bridge Club