Fourth suit forcing (also referred to as fourth suit artificial; [1] abbreviated as FSF or 4SF) is a contract bridge convention that allows responder to create, at his second turn to bid, a forcing auction. A bid by responder in the fourth suit, the only remaining unbid suit, is artificial indicating that responder has no appropriate alternate bid, remains interested in the potential for a game contract and asks opener to bid again to show additional features.
In the card game contract bridge, a forcing bid is any call that obliges the partner to bid over an intermediate opposing pass. Owing to the partnership's bidding system or a bridge convention, partner must "keep the bidding open", i.e. not pass, thereby preventing his left-hand opponent from ending the auction with a pass and enabling the "forcing bidder" to bid further.
Opener responds to the fourth suit forcing by (in prioritised order):
Fourth suit forcing is minimally forcing for one round and usually forcing to game - partnership agreement is required. Whether or not the convention is applicable if the fourth-suit bidder is a passed hand is also a matter of partnership agreement; there is no consensus amongst experts on the options as to its use being non-forcing, forcing, or forcing only after a reverse. [1]
It requires an invitational hand with at least 10 points, or 12-13 upwards if it is game-forcing and opener has not shown any extra strength.
In contract bridge, various bidding systems have been devised to enable partners to describe their hands to each other so that they may reach the optimum contract. Key to this process is that players evaluate and re-evaluate the trick-taking potential of their hands as the auction proceeds and additional information about partner's hand and the opponent's hands becomes available.
The convention was introduced by the British bridge author Norman Squire and is adopted by the majority of partnerships playing at competitive levels. Useful with strong game-going hands where responder has no natural forcing rebid, it is a type of game try bid.
A game try in the card game of bridge is a bid that shows interest in bidding a game and asks partner to help in making the decision.
Corollary to fourth suit forcing
One of the negative inferences of fourth suit forcing is that all other simple jumps by responder at his second turn are invitational and not game forcing. In the unopposed sequence 1 club -- 1 heart -- 1 spade: a jump by responder to two no-trumps, three clubs, three hearts or three spades are all invitational and not forcing. They suggest 10-12 HCP. Conversely, going through 2 diamonds, the fourth suit, lets you make any of those calls at your next turn and have the call be forcing.
Fourth suit by a passed hand
Entirely different considerations apply when the fourth suit bidder is a passed hand. Since the bidder is limited in strength through failure to open, he cannot force his partner to keep bidding, but the fact that opener has rebid at all says that opener is either very shapely or has more than minimum values for an opening bid.
Opener may pass a bid of the fourth suit. If opener continues with 2NT, which will show values, responder is expected to raise to 3NT with nothing more, by way of shape, to show. Opener will generally pass a rebid in responder's second suit, knowing the hand opposite is very shapely and weak. With ill-fitting hands, lacking game going values, a bid in the fourth suit will often allow the partnership to subside in a playable contract in a reasonable fit, at the two-level. See example 3.
| North | South |
|---|---|
| 1♦ | 1♠ |
| 2♣ | ? |
South holds ♠ A Q 8 6 2 ♥ 8 4 3♦ Q 7 ♣ A 6 5 in the auction at left.
After 2♣ by North, South sees there is likelihood for game given that the partnership has bid three suits bid and holds around 24-26 high card points. However, he does not have a good natural bid available; each would give partner the impression of stronger support than he has, and might lead to a poor choice of contract.
South instead bids the fourth suit (fourth suit forcing), i.e. 2♥, to indicate that he believes they have values for game, that he lacks a stopper in hearts needed for notrumps and that he has no viable bid in any of the other suits. Depending on partnership agreement, this 2♥ bid may be either forcing for one round, or forcing to game.
| North | South |
|---|---|
| 1♣ | 1♥ |
| 1♠ | 2♦ |
| 2♥ | 2♠ |
The fourth suit forcing approach in conjunction with the principle of fast arrival allows the partnership to create a game-forcing auction at low level that leaves ample room to explore for slam.
In the game of contract bridge, the principle of fast arrival is a bidding treatment widely used in game forcing auctions whereby:
Here, the 2♠ bid denotes a four card spade support and a hand too strong for a fast-arrival bid of 4♠. This assumes the partnership are playing all FSF bids, at 2 or 3 level, as forcing to game. If playing that a 2 level FSF bid is forcing for one round only, responder will need to jump to 3♠ on the third round to create the game force.
The following is an example of a fourth-suit bid by a passed hand being non-forcing; this partnership agreement allows opener to make a preference bid by either passing or returning to partner's first suit.
| ♠ | KQ754 | W E | ♠ | AJ |
| ♥ | 65 | ♥ | AK743 | |
| ♦ | KQ75 | ♦ | 42 | |
| ♣ | 82 | ♣ | QJ93 |
| West | North | East | South |
|---|---|---|---|
| Pass | Pass | 1♥ | Pass |
| 1♠ | Pass | 2♣1 | Pass |
| 2♦2 | Pass | 2♠3 | Pass |
| Pass4 | Pass |
1 Just strong enough to justify another bid over West's passed hand response.
2 Natural, not forcing, more flexible than 2NT.
3 With three-card support East would give strong, jump preference.
4 No primary fit has been uncovered, to bid on would jeopardise a plus score.
The side has done well to avoid a very poor 25 point 3NT contract.
Stayman is a bidding convention in the card game contract bridge. It is used by a partnership to find a 4-4 or 5-3 trump fit in a major suit after making a one notrump (1NT) opening bid and it has been adapted for use after a 2NT opening, a 1NT overcall, and many other natural notrump bids.
Standard American is a bidding system for the game of bridge widely used in North America and elsewhere. Owing to the popularization of the game by Charles Goren in the 1950s and 1960s, its earliest versions were sometimes referred to simply as 'Goren'. With the addition and evolution of various treatments and conventions, it is now more generally referred to as Modern Standard American. It is a natural bidding system based on five-card majors and a strong notrump; players may add conventions and refine the meanings of bids through partnership agreements summarized in their convention card. One standardised version, SAYC, is widely used by casual partnerships and in online bridge.
2/1 game forcing is a bidding system in modern contract bridge structured around the following responses to a one-level opening bid:
Acol is the bridge bidding system that, according to The Official Encyclopedia of Bridge, is "standard in British tournament play and widely used in other parts of the world". It is basically a natural system using four-card majors and, most commonly, a weak no trump.
Polish Club is a bridge bidding system which was developed in Poland, where it is the most popular bidding system, and which is also used by players of other countries. It is a type of small club system.
The forcing notrump is a bidding convention in the card game of bridge.
The Jacoby transfer, or simply transfers, in the card game contract bridge, is a convention in Standard American bidding systems initiated by responder following partner's notrump opening bid that forces opener to rebid in the suit ranked just above that bid by responder. For example, a response in diamonds forces a rebid in hearts and a response in hearts forces a rebid in spades. Transfers are used to show a weak hand with a long major suit, and to ensure that opener declare the hand if the final contract is in the suit transferred to, preventing the opponents from seeing the cards of the stronger hand.
Zar Points (ZP) is a statistically derived method for evaluating contract bridge hands developed by Zar Petkov. The statistical research Petkov conducted in the areas of hand evaluation and bidding is useful to bridge players, regardless of their bidding or hand evaluation system. The research showed that the Milton Work point count method, even when adjusted for distribution, is not sufficiently accurate in evaluating all hands. As a result, players often make incorrect or sub-optimal bids. Zar Points are designed to take many additional factors into consideration by assigning points to each factor based on statistical weight. While most of these factors are already implicitly taken into account by experienced players, Zar Points provides a quantitative method that allows them to be incorporated into bidding.
Developed by Oswald Jacoby, Jacoby 2NT is a bridge convention in which a bid of two notrump (2NT) over partner's opening bid of one heart or one spade shows a hand with both
Multi 2 diamonds, or simply Multi, is a contract bridge convention whereby the opening bid of 2♦ shows multiple types of hands, which always includes a weak-two bid in either major suit, while the additional meaning may be a strong balanced hand, or a 20-22 three suiter. The inherent ambiguity as to both suit and strength makes it a powerful and popular convention capable of seriously disrupting the opponents' bidding.
A reverse, in the card game contract bridge, is a bidding sequence designed to show additional strength without the need to make a jump bid; specifically two suits are bid in the reverse order to that expected by the basic bidding system. Precise methods and definitions vary with country, bidding system and partnership agreements.
EHAA is a highly natural bidding system in contract bridge characterized by four-card majors, sound opening bids, undisciplined weak two-bids in all four suits and a mini notrump, usually of 10–12 high card points.
New Minor Forcing (NMF), is a contract bridge bidding convention used to find a 5-3 or 4-4 major suit fit after a specific sequence of bids in which opener has rebid one notrump. The convention is triggered by responder at his second turn by an artificial bid of two in an unbid minor; it requires that he hold five cards in the major he has previously bid and an unlimited hand ranging in value from at least game invitational strength to that sufficient to have interest in slam; he may also hold four cards in the other major. Accordingly, there are six bidding sequences in which the New Minor Forcing bid may be applied:
Bridge base basic, also known as BBO basic, is a bidding system for the game of bridge based on Standard American Yellow Card. It is simplified, suitable for beginners, and widely used in internet bridge particularly on Bridge Base Online. It is taught in Fred Gitelman's educational software called Learn to Play Bridge that is available as a free download from the American Contract Bridge League's website.
Mini-Roman or Mini-Roman 2 Diamonds is contract bridge convention whereby the opening bid of 2♦ shows a three suited hand and 11-15 high card points (HCP). The convention is meant to help responder to judge, more quickly, the right level of the contract and the best trump suit.
XY Notrump is a bidding convention in contract bridge.
Transfer Walsh is a bidding convention used in contract bridge. After a 1♣ opening bid, responses of 1♦ and 1♥ show heart and spade suits respectively. The "Walsh" terminology refers to the fact that these bids may conceal an equal or longer diamond suit. It allows opener to play a greater proportion of major-suit and no-trump contracts, particularly when using five-card majors.
OKbridge 2/1 is a duplicate bridge bidding system combining two-over-one game-forcing and Walsh bidding methods.
XYZ is a bidding convention in contract bridge.