An excellent way to find your 5-3 fits in a competitive auction. This convention was invented by Eric Rodwell.
What does a Support Double show?
3-card support for responder's major.
Are Support Doubles used if RHO overcalls 1NT or cue-bids the suit you opened?
In addition to showing 3-card support, what does a Support Double say about opener's hand?
A Support Double does NOT indicate: the strength of opener's hand, his distribution, or the quality of his trumps. Not to worry. As the examples will illustrate, having a good auction after a Support Double is very do-able.
What happens if RHO makes a takeout double?
With 3-card support, opener will redouble. If you play Support Doubles, there's no reason not to play Support Redoubles.
Keep in mind: You won't always have an 8-card fit in a major. When responder doesn't have a 5-card major, he'll have to decide whether to: bid notrump, show another suit, or play in a 4-3 fit. For more on this issue, see hands 2-4 coming up.
East has bid a spade and may have 4 or 5 or more. Perhaps with 4 he would have made a negative double but perhaps he felt he had the wrong hand for a negative double. West made a support double to show 3 card support for spades. Had he raised to 2 instead it would have shown 4 card support.
Opener holds: AT2 72 AT KQ7543 and opens 1 next bidder overcalls 1
Responder holds: KQJ43 954 853 A6 and bids 1 next bidder raises opponents 1 to 2 and opener doubles a (Support Double). opponent passes and Responder knows you have an 8-card fit and so bids 3 which you raise to 4
Opener holds: JT5 KT2 AKQ5 AJ4 and opens 1
Responder holds: A842 J6 JT2 8762 after opponent passes, responder bids 1 and the opponent bids 2. Opener Doubles (Support Double) showing 3-card support (Alert) this is passed back to responder who decides to try the 4-3 fit and so bids 2. This is passed back to you. With a balanced hand and extra points you try 2NT which is passed out. Responder has a minimum.
West doubled to show 3 card support but decides he does not want to play in a 4-3 fit. When you play in a 4-3 fit you would like to have a short side suit in the same hand as the 3-card support so you can ruff with the short trump hand. In this case, West wants to show his strong hand by bidding 2NT. With a minimum, responder passes.
Opener holds: K65 AK864 A642 7 and open 1
Responder holds: T873 -- 9753 AQJ98 and after the opponent passes, responder bids 1. The next opponent 1NT (natural and strong or sandwich, we don't care). Opener Doubles (Support Double). Next opponent passes and responder shows his longer side suit by bidding 2. Next opponent passes and opener bids 2, suggesting short clubs and diamonds as a side suit. This fits well with responders hand and it is passed out.
Remember, Support Doubles do apply after NT interference. West shows 3-card support for East but East has a weak spade suit and longer clubs and thus rebids clubs. West suggests diamonds and East agrees by passing.
Opener holds: A764 AJ9 6 AK984 and opens 1
Responder holds: T853 T753 KQ7 J3 and after the next opponent passes responder bids 1. Next opponent bids 2. Opener Doubles (Support Double). Next opponent passes and responder settles for a 4-3 fit by bidding 2. Next bidder passes and opener suggests 2.This is passed out.
Opener shows 3-card support for hearts and then shows 4 spades and a good hand. Since responder has a fit and a weak hand he passes. How else would you find the spade fit? It would be wrong for opener to bid 2 immediately because responder could have 5 or more hearts and they would miss the heart fit.
Opener holds: A764 AJ9 6 AK984 and opens 1
Responder holds: K53 KT863 T97 63 and after the next opponent passes he bids 1. The next opponent bids 2 and opener Doubles (Support Double). This is passed back to responder who bids 2. Next opponent passes and opener suggests 2. Next opponent passes and responder shows his 5-card heart suit with a minimum by bidding 3. Opener has extra points and a singleton diamond and raises to 4
Same cards for opener as hand 4 but opener's hand gets better when he finds they have an 8-card heart fit. Responder bids 3 showing 5 hearts and opener bids game.
Opener holds: Q42 AK42 AQJ83 9 and bids 1
Responder holds: KJ986 96 K72 763 and after the next opponent passes he bids 1. Next opponent Doubles and opener ReDoubles (Support Redoublel). Next opponent bids 2 and responder freely bid 2. After the next bidder passes, Opener bids 4.