Sunday, November 28, 2010

Fourth Suit Forcing Auctions

Fourth suit forcing to game is something most players play nowadays but I think many people don't know some of the implications of bidding fourth suit. Why do we bid fourth suit forcing? Because we want to be in game but don't know what strain we should be in or because we want to make a forcing raise but bidding 2, 3, or 4 of the suit would all be passable, and/or because we want to make a slam try.

Take this auction for example: 1C-1H-1S-2D-2NT-3S. Opener has a balanced minumum with 4 spades and a diamond stopper. Many people do not know what responder is showing here. He is making a slam try in spades. He could not bid 2S (nonforcing), 3S (inv), or 4S (sign off) so the only way to raise spades and have it be forcing is to bid 4th suit and then bid 3S. A good hand for this would be: AJxx, AKxx, Kxx, Ax. Take out a king and it's a simple 4S bid over 1S. Likewise, responder has to bid fourth suit to make a forcing club or heart raise.

As with new minor forcing, many people think of 4th suit as just showing a good hand with a 5 card major, which it frequently is, but people need to keep in mind that it could be a hand with too much to just jump to game, and/or a forcing hand that does not have the 4th suit stopped.


  1. I think Megan might have made that 3S bid with something like AJx AKxxx x xxx, suggesting the 4-3 spade fit with a ruffing value instead of a shaky 3NT. We tend not to raise right away with only three trumps (especially when we have a good five-card suit of our own). I think that sequence might be two-way--you can clarify if you have the slam-try hand with your next bid.

    Or you can play XYZ, as we have started doing...

  2. Yes, that is a possible and sensible way to play that sequence. XYZ is very useful and clears up many ambiguities that go along with awkward 4th suit forcing auctions, but I want people to have a better idea of what is standard.