Sacrifice (bridge)
Encyclopedia
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. In rubber bridge
, a sacrifice can be also made in an attempt to prevent the opponents scoring a game or rubber on the expectation that subsequent deals can be won to offset the loss of points. Owing to the difference in the methods of scoring, a sacrifice in rubber bridge is much less likely to be advantageous.
, making a game contract yields 600 or 620 points vulnerable and 400 or 420 points non-vulnerable, depending upon the and assuming no . Accordingly, a sacrifice will turn out profitable if the resultant loss in points is less than these amounts.
Determination of the most number of tricks than can be lost to satisfy this condition is dependent upon the of each partnership, i.e. whether one, the other, both or neither are vulnerable. The determination is also based upon the assumption that the opposition will likely double the sacrifice bid thereby increasing the penalty points. The table at left summarises the various scenarios and outcomes.
In summary, when the opponents are likely to make a game contract, a sacrifice bid is viable (i.e. one will still receive a positive relative duplicate score) if one can go down no more than 3 tricks if vulnerability is favourable, 2 if equal and 1 if unfavourable.
Similar reasoning can be drawn for potential and contracts.
game in advance:
As seen in the table above, vulnerability significantly affects the sacrifice: success is most likely if the opponents are vulnerable but the sacrificing side is not. At equal vulnerabilities, sacrifices are less frequent, and vulnerable sacrifices against non-vulnerable opponents are very rare and often not bid deliberately. Also, the specific duplicate scoring method affects the tactics of sacrifice – at matchpoint scoring, −500 or −800 (down 3 or 4) against −620 is a 50/50 bet on a top or a bottom score, but at international match points (IMPs) it can gain 3 IMPs (120 difference) but lose 5 (180 difference), making it less attractive.
However, if it turns out that the sacrificing side misjudged, and that the opponents' contract was unmakeable (or unlikely to make), the sacrifice is referred to as a false or phantom one. A false sacrifice can cost heavily, as the sacrificing side has in effect turned a small plus into a (potentially large) minus score.
The Law of total tricks
can be a guideline as to whether the sacrifice can be profitable or not.
Sacrifices are practically always made in a suit contract; sacrifices in notrump are extremely rare, but can occur, as in the following deal:
The bidding starts:
1. Michaels cuebid
, indicating both majors.
South can see that East-West have a huge spade fit and that it's quite possible that they can make 4. However, the best bet seems to be 4NT rather than 5, since it requires a trick less, while there's not much indication that 5 would provide more tricks than 4NT. Indeed, 4NT is down one and 5 down two.
Duplicate bridge
Duplicate bridge is the most widely used variation of contract bridge in club and tournament play. It is called duplicate because the same bridge deal is played at each table and scoring is based on relative performance...
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. In rubber bridge
Rubber bridge
Rubber bridge is a form of contract bridge and is played with four players. It is most often played for fun but is also played seriously for money...
, a sacrifice can be also made in an attempt to prevent the opponents scoring a game or rubber on the expectation that subsequent deals can be won to offset the loss of points. Owing to the difference in the methods of scoring, a sacrifice in rubber bridge is much less likely to be advantageous.
Scoring context
In duplicate bridge scoringBridge scoring
Bridge scoring is keeping score in contract bridge. There are two common methods of scoring a single deal: "duplicate" and "rubber" scoring. These two methods are similar, but differ in how the components of the score are accumulated....
, making a game contract yields 600 or 620 points vulnerable and 400 or 420 points non-vulnerable, depending upon the and assuming no . Accordingly, a sacrifice will turn out profitable if the resultant loss in points is less than these amounts.
| Opponents' game points | Undertrick penalty points in a doubled contract |
|||||||
|---|---|---|---|---|---|---|---|---|
| Vulnerability | Points | Vulnerable undertricks |
Not vulnerable undertricks |
|||||
| 1 | 2 | 3 | 1 | 2 | 3 | 4 | ||
| Vulnerable | 600 or 620 | 200 | 500 | 800 | 100 | 300 | 500 | 800 |
| Not vulnerable | 400 or 420 | 200 | 500 | 800 | 100 | 300 | 500 | 800 |
In summary, when the opponents are likely to make a game contract, a sacrifice bid is viable (i.e. one will still receive a positive relative duplicate score) if one can go down no more than 3 tricks if vulnerability is favourable, 2 if equal and 1 if unfavourable.
Similar reasoning can be drawn for potential and contracts.
Strategy
A sacrifice most often occurs when both sides have found a fit during bidding (8 cards or more in a suit), but the bidding indicates that the opponents can make a game or slam contract. Also, it is possible to perform an advance sacrifice, when it is more or less clear that the opponents have a fit somewhere and greater strength. For example, after the partner opens 1 and RHO doubles, the following hand is suitable for a bid of 5, outbidding opponents' major suitMajor 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:
As seen in the table above, vulnerability significantly affects the sacrifice: success is most likely if the opponents are vulnerable but the sacrificing side is not. At equal vulnerabilities, sacrifices are less frequent, and vulnerable sacrifices against non-vulnerable opponents are very rare and often not bid deliberately. Also, the specific duplicate scoring method affects the tactics of sacrifice – at matchpoint scoring, −500 or −800 (down 3 or 4) against −620 is a 50/50 bet on a top or a bottom score, but at international match points (IMPs) it can gain 3 IMPs (120 difference) but lose 5 (180 difference), making it less attractive.
However, if it turns out that the sacrificing side misjudged, and that the opponents' contract was unmakeable (or unlikely to make), the sacrifice is referred to as a false or phantom one. A false sacrifice can cost heavily, as the sacrificing side has in effect turned a small plus into a (potentially large) minus score.
The Law of total tricks
Law of total tricks
In contract bridge, the Law of total tricks is a guideline used to help determine how high to bid in a competitive auction. It is not really a law but a method of hand evaluation which describes a relationship that seems to exist somewhat regularly...
can be a guideline as to whether the sacrifice can be profitable or not.
Sacrifices are practically always made in a suit contract; sacrifices in notrump are extremely rare, but can occur, as in the following deal:
The bidding starts:
| West | North | East | South |
|---|---|---|---|
| 1 | |||
| 21 | 2NT | 4 | ? |
1. Michaels cuebid
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...
, indicating both majors.
South can see that East-West have a huge spade fit and that it's quite possible that they can make 4. However, the best bet seems to be 4NT rather than 5, since it requires a trick less, while there's not much indication that 5 would provide more tricks than 4NT. Indeed, 4NT is down one and 5 down two.