Preempt
Encyclopedia
Preempt is a bid in contract bridge
Contract bridge
Contract bridge, usually known simply as bridge, is a trick-taking card game using a standard deck of 52 playing cards played by four players in two competing partnerships with partners sitting opposite each other around a small table...

 whose primary objectives are (1) to thwart opponents ability to bid to their best contract, with some safety, and (2) to fully describe one's hand to one's partner in a single bid. A preemptive bid is usually made by jumping, i.e. skipping one or more bidding levels. Since it deprives the opponents of the bidding space, it is expected that they will either find a wrong contract (too high or in a wrong denomination) of their own, or fail to find any. A preemptive bid often has the aim of a sacrifice
Sacrifice (bridge)
A sacrifice is a deliberate bid of a contract in duplicate bridge that is unlikely to make in the hope that the points will be less than the points likely to be gained by the opponents in making their contract...

, where a partnership bids a contract knowing it cannot be made, but assumes that (even when doubled), the penalty will still be smaller than the value of opponents' bid and made contract.


Whenever you can describe your hand completely with a single bid, you should do so.

-- Dean Panagopoulos, Bridge Teacher and Director of The Bridge Spot, Woburn, Massachusetts

Preemptive opening bids and preemptive overcalls

A preemptive opening bid is an opening bid on level 2 or higher, typically made with a weak hand containing a long, strong suit. Preemptive opening bids on level 3 and higher are common for most bidding system
Bidding system
A bidding system in contract bridge is the set of agreements and understandings assigned to calls and sequences of calls used by a partnership, and includes a full description of the meaning of each treatment and convention...

s in the world. For example, the hand of is a typical 3 opener. The bid is made on presumption that, without any additional tricks from the partner, at least 6 tricks can be taken with hearts as trump, and the potential penalty of 500 points in 3 doubled is smaller than the value or opponents' likely game or slam (cca. 600 and 1400 points respectively (when they are vulnerable)).

A preemptive overcall is a jump overcall (so 2 is preemptive over 1 but not over 1) that is otherwise identical to a preemptive opening bid.

A preemptive opening bid usually shows at least six (6) high card points and a suit with six or more cards headed by honors (typically either K-Q or better or Q-J-10 or better) but less than a normal opening bid. Some textbooks recommend the "rule of 2 and 3":
  • At favorable vulnerability (non-vulnerable against vulnerable opponents), open the bidding on the level where the contract would be set 3 tricks (see losing trick count), without help from the partner
  • At equal vulnerability, bid on the level where the contract would be set 2 tricks


The idea is that a defeat, if doubled, should cost less than the value of opponents' game.
Undertricks Vulnerability
our defeat/their game
NV/V NV/NV V/V V/NV
3 500/600 500/400 800/600 800/400
2 300/600 300/400 500/600 500/400
1 100/600 100/400 200/600 200/400

(Situations where the preempt is indicated are marked bold)

Obviously, preempting at unfavorable vulnerability is dangerous; such preempts, if ever, are often made with an intention of making the contract, and the long suit is often backed up by an unusual distribution, such as 7-4-2-0.

The same requirements generally hold for preemptive overcall
Overcall
In contract bridge, an overcall is a bid made after an opening bid has been made by an opponent; the term refers only to the first such bid. A direct overcall is a bid made directly over the opening bid by right-hand opponent; an overcall in the 'last seat' is referred to as a balancing...

s. However, they are normally loosened in third seat, when the partner has already passed, so the opening bidder can be sure that the only side preempted are the opponents, and thus can bid with better or thinner values.

An alternative approach is to bid the level suggested by the Law of Total Tricks, with the assumption that partner's hand has one third of the remaining trumps. Using this approach,
  • If playing "weak two bid
    Weak two bid
    The Weak two bid is a common treatment used in the game of contract bridge, where a jump bid of two of a suit signifies a weak hand with a long suit. It is a form of preemptive bid...

    s" (now standard), bid at the "two" level with six cards of the suit (except in clubs),
  • Bid at the "three" level with seven cards of the suit, and
  • Bid at the "four" level with eight or nine cards of the suit.


Note that, in the "Weak Twos" convention, an opening bid of two clubs
Strong two clubs
In most natural bridge bidding systems, the opening bid of 2 is used exclusively for hands too strong for an opening bid at the one-level. Systems that incorporate a strong 2-club opening bid include modern Standard American, standard Acol, 2/1 game forcing and many others...

 (2) is strong and artificial, typically showing at least 22 HCP, and thus is not available for preemption for hand with six clubs. Thus, some partnerships bid 3 with good preemptive hand (typically at least 8 HCP) that has only six clubs. Many partnerships that use an opening bid of 2 as a conventional bid will likewise bid 3 with a good preemptive hand that has only six diamonds.

Obviously, preempts in the fourth seat are very rare, as there is nobody to preempt: they do occur occasionally, though, e.g. when the player has a near-opening bid with a long suit, but is reluctant to open on level 1 for fear of being outbid by perceived opponents' major. For example, the hand might reasonably open 3 in the fourth seat, hoping to silence the opponents' with their spades and/or hearts.

A preemptive bidder bids again only if his or her partner makes a conventional bid that requires a response.

Gambling 3NT
Gambling 3NT
Gambling 3NT is a preemptive opening bid. The bid is used to describe a hand containing a minor suit of at least 7 cards in length and headed by the AKQ at minimum...

 opening bid is often used to preempt with a solid minor suit.

If Namyats
Namyats
In the cardgame bridge Namyats denotes the conventional agreement to open hands with a long major suit that are too strong for a direct preemptive opening with a 'two-under' transfer bid. The method was originally named 'Four Club and Four Diamond Opening Transfers', and is also referred to as...

 is used, 4 and 4 are no longer available for preempts.

Other preempts

A partnership can preempt the opponents cooperatively, having discovered that they have an excellent suit
Suit (cards)
In playing cards, a suit is one of several categories into which the cards of a deck are divided. Most often, each card bears one of several symbols showing to which suit it belongs; the suit may alternatively or in addition be indicated by the color printed on the card...

 fit but not much overall defensive strength. For example, after the partner opens 1 and RHO doubles, the following hand is suitable for a bid of 5, outbidding opponents' major suit
Major suit
In the card game contract bridge, the major suits are spades and hearts . The major suits are of prime importance for tactics and scoring as they outrank the minor suits while bidding and also outscore them...

 game in advance:
In a more general sense, even low-level and non-jump bids can have a preemptive value if they deprive the opponents of bidding suits that they could otherwise bid on level 1 or 2. For example, weak 1 notrump (characteristic for Acol
Acol
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 named after the Acol Bridge Club, previously located on Acol Road in London NW6, where the system started to evolve...

 system) opening takes up entire level 1 from the opponents, who could bid their long suit on level 1 had the opening been 1 of a minor
Minor suit
In contract bridge the minor suits are diamonds and clubs . They are given that name because contracts made in those suits score less than contracts made in the major suits , and they rank lower in bidding. In particular, one can make game with a bid of 4 in a major suit, while a bid of 5 is...

, like in Standard American
Standard American
Standard American is a common bidding system for the game of bridge in the United States, also widely used in the rest of the world. This system, or a slight variant, is learned first by most beginners in the U.S. and may be referred to as 'Goren'; a dominant version used in on-line computer...

 bidding. However, there is always the danger that the preempting side could preempt themselves, taking up their own bidding space that could be used for constructive bidding. For example, four-card major openings have a more preemptive effect compared with five-card major openings, but also carry less precise information, as the partner should not support the opened suit without at least 4 cards; that could result in missing a partial contract or even a game.

Many partnerships also use Michaels Cue Bids preemptively. A Michaels Cue Bid
Michaels cuebid
The Michaels cuebid is a conventional bid used in the card game contract bridge. First devised by Mike Michaels of Miami Beach, it is an overcaller's cuebid in opponent's opening suit and is normally used to show a two-suited hand with at least five cards in each suit and eight or more points.After...

 is a bid of two of a suit in which an opponent has bid one that promises two five-card suits including the unbid majors and, in most partnerships, at least seven or eight HCP. Thus, either 1-2 or 1-2 promises both five hearts and five spades, 1-2 promises five spades and either five clubs or five diamonds, and 1-2 promises five hearts and either five clubs or five diamonds. Over a Michaels Cue Bid in either major suit, partner's response of 2NT asks the Micheals bidder to bid the minor suit. If the Michaels bidder has a strong hand, the Michaels bidder can show the strength by rebidding an agreed suit at a higher level.

Responses

Since the preempter has a weak hand, responder will pass most of the time. However, responder also has the following options:
  • Raise opener's suit: Usually done to further the preempt with 3-card support (or jump with even more support), making it even more difficult for the opponents to compete. However, a raise to game can also be made with a good hand without support for opener if responder expects to make the contract. Opener must pass after any raise by partner.
  • 3NT: To play. Responder expects to make 9 tricks either by running partner's suit or his own. If responder expects to run opener's suit, support is needed as opener may not have outside entries to his hand. Also, responder should have stoppers in all suits.
  • Bid a new suit below game: Forcing, with at least 5 cards in the suit bid. Responder raises with 3-card support and rebids his own suit without support.


Over a preemptive opening bid or overcall at the "two" level, many partnerships use the 2NT response to ask for more information about the preemptive hand. In the Standard American Yellow Card (SAYC) bidding system, the preemptive bidder responds by bidding another suit containing an ace or a king or, lacking such a suit, by rebidding the suit of the preempt at the "three" level. In either case, the responder can then place the final contract.

The Ogust convention
Ogust convention
Ogust is a bridge convention used after a weak two bid by responder to gauge the strength of the weak two bidder's hand. This convention is named after Harold A...

provides a more informative set of responses to the 2NT inquiry.
  • 3 shows a "minimal" preempt (typically 6-7 HCP) and a "poor" suit.

  • 3 shows a "minimal" preempt and a "good" suit.

  • 3 shows a "strong" preempt (typically 8-10 HCP) and a "poor" suit.

  • 3 shows a "strong" preempt and a "good" suit.

  • 3NT shows that the preempt suit is "solid" (headed by AKQ).


The differentiation between "minimal" and "strong" preempts and between "poor" and "good" hands is a matter of partnership agreement, and typically depends upon the partnership's strictness in preemptive bidding. Partnerships that are very strict typically regard a suits with only two of the top three or three of the top four honors as "poor" while partnerships that preempt with poorer suits may regard such suits as "good." Hands that respond 3 or 3NT typically do not have outside entries, as their long suits contain nearly all of their high card points.

The Law of Total Tricks

Many players now use the "Law of Total Tricks" as a "thumb rule" for preemptive and sacrificial bidding. Bids dictated the Law of Total Tricks are often sacrificial, but nonetheless produce consistent "top half" results with proper play.,


The Law of Total Tricks:

In a competitive auction, it is safe to bid a number or total tricks equal to the number of trumps in the combined hands of both partners.


When viewed in context of the Law of Total Tricks, normal preemptive opening bids, described above, basically assume that the preemptive bidder's partner possesses two of the five to seven outstanding cards of the long suit—mathematically, the "expected" number based on equiprobable distribution of the missing cards. Thus, the Law of Total Tricks implies that the preemptive opener's partner can safely raise the preemptive opening bid by the number of cards in excess of two in the named suit (for example, raise an opening bid of 3, which promises seven hearts, to 4 with three hearts (7+3=10 total tricks) or to 5 with four hearts (7+4=11 total tricks)), regardless of the responder's high card points.

The limit raises and preemptive raises of major suits in the Standard American Yellow Card bidding system also conform to the Law of Total Tricks. By opening a major suit normally, the opening bidder promises at least five cards of the major suit. A "limit" raise, which is a response of three of the opener's suit, requires ten to twelve high card points and four cards in the responder's suit, for a total of nine. Likewise, a preemptive raise, which is a bid of four of the opener's suit, requires five cards in that suit, for a total of ten. The Law of Total tricks allows the opening bidder to raise such responses by the number of cards in excess of five in that suit.
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