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Sacrifice (bridge)

In duplicate bridge, a sacrifice (a save in common usage) is a deliberate bid of a contract that is unlikely to make in the hope that the penalty points will be less than the points likely to be gained by the opponents in making their contract. In rubber bridge, a sacrifice is an attempt to prevent the opponents scoring a game or rubber on the expectation that positive scores on subsequent deals will offset the negative score.

Owing to the difference in the methods of scoring between duplicate and rubber bridge, a sacrifice bid in rubber bridge is much less likely to be advantageous[1] and so strategies differ between the games. Comparable strategy differences exist between Matchpoints scoring and IMPs scoring games.

Scoring context edit

Sacrificing against game contracts edit

Sacrificing Against a Game Contract
Opponents'
probable game points
Our probable penalty
points in a doubled contract
Their
vulnerability
Points Tricks down when
we are vulnerable
Tricks down when
we are not vulnerable
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 duplicate bridge scoring, if the opponents bid and make a game contract, it yields them 600 or 620 points when they are vulnerable and 400 or 420 points when they are not vulnerable, depending upon the strain and assuming no overtricks. Accordingly, a sacrifice will be advantageous if the resultant loss in points is less than these amounts.

Determination of the most number of tricks that can be lost to satisfy this condition is dependent upon the relative vulnerability 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 double the sacrifice bid thereby increasing the penalty points. The table at the left summarises the various scenarios and outcomes.

In summary, when the opponents are likely to make a game contract, a sacrifice bid which is doubled is viable (i.e. one will still receive a positive relative duplicate score) if one can go down no more than:

  • three tricks if vulnerability is favourable (shown in green)
  • two if vulnerability is equal (shown in yellow)
  • one if vulnerability is unfavourable (shown in red)

Similar reasoning can be drawn for sacrifices against potential slam and partscore contracts and cases where one assumes that the contract will not be doubled.

Sacrificing against small slam contracts edit

Sacrificing Against Small Slam Contracts
Opponents'
expected game points
Sacrificer's expected maximum
penalty points and undertricks
Vulnerability Contract Points Not vulnerable Vulnerable
Points Undertricks Points Undertricks
Not vulnerable 6NT 990 800 4 800 3
6 or 6 980
6 or 6 920
Vulnerable 6NT 1440 1400 6 1400 5
6 or 6 1430
6 or 6 1370 1100 5 1100 4

When the opponents are likely to make a small slam contract, a sacrifice bid which is doubled is viable if one can go down no more than

  • six tricks if relative vulnerability is favourable against a small slam in a major or notrump
  • five tricks if relative vulnerability is favourable against a small slam in a minor
  • five tricks if relative vulnerability is equal where both sides are vulnerable against a small slam in a major or notrump
  • four tricks if relative vulnerability is equal where both sides are vulnerable against a small slam in a minor
  • four tricks if relative vulnerability is equal where both sides are not vulnerable against any small slam
  • three tricks if relative vulnerability is unfavourable against any small slam

Sacrificing against grand slam contracts edit

Sacrificing Against Grand Slam Contracts
Opponents'
expected game points
Sacrificer's expected maximum
penalty points and undertricks
Vulnerability Contract Points Not vulnerable Vulnerable
Points Undertricks Points Undertricks
Not vulnerable 7NT 1520 1400 6 1400 5
7 or 7 1510
7 or 7 1440
Vulnerable 7NT 2220 2000 8 2000 7
7 or 7 2210
7 or 7 2140

When the opponents are likely to make a grand slam contract, a sacrifice bid which is doubled is viable if one can go down no more than

  • eight tricks if vulnerability is favourable
  • seven tricks if both vulnerable
  • six tricks if both not vulnerable
  • five tricks if vulnerability is unfavourable.

Strategy edit

A sacrifice most often occurs when both sides have found a fit during bidding (eight 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 suit game in advance:

 8 3  4  Q 10 8 5 4 2  Q J 6 4

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 three or four) against −620 is a 50/50 probability for a top or 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:

A 6
K 8 7 4
J 9 7 4
Q J 5
Q 10 8 5 3

N

W               E

S

K J 9 7 2
A Q J 6 3 10
5 2
K 8 4 10 9 6 3 2
4
9 5 2
A K Q 10 8 6 3
A 7

The bidding starts:

West North East South
1
21 2NT 4 ?

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 sacrifice seems to be 4NT rather than 5; it requires a trick less and there is no indication that 5 would provide more tricks than 4NT. Indeed, 4NT is down one and 5 down two.

Other considerations in sacrifices edit

The scoring matters a lot in sacrifices. Matchpoints scoring vs. IMP scoring makes a very significant difference in sacrifice decisions.

Kit Woolsey suggests that the following three conditions should all be met for a sacrifice to make sense in Matchpoint scoring:

  • The field is going to bid the game the opponents reached.
  • The said game is very likely to make.
  • Your doubled sacrifice is likely to not go down too much (i.e. maximum 1 down in unfavorable vul, max 2 in equal, and max 3 in favorable. Slam values are much higher) [2]

See also edit

References edit

  1. ^ Francis, Henry G.; Truscott, Alan F.; Francis, Dorthy A., eds. (2001). The Official Encyclopedia of Bridge (6th ed.). Memphis, TN: American Contract Bridge League. p. 402. ISBN 0-943855-44-6. OCLC 49606900.
  2. ^ Woolsey, Kit (2015). Matchpoints (2nd ed.). Bridge Winners Press. p. 289. ISBN 978-0-9905229-5-9.

sacrifice, bridge, other, uses, sacrifice, disambiguation, duplicate, bridge, sacrifice, save, common, usage, deliberate, contract, that, unlikely, make, hope, that, penalty, points, will, less, than, points, likely, gained, opponents, making, their, contract,. For other uses see Sacrifice disambiguation In duplicate bridge a sacrifice a save in common usage is a deliberate bid of a contract that is unlikely to make in the hope that the penalty points will be less than the points likely to be gained by the opponents in making their contract In rubber bridge a sacrifice is an attempt to prevent the opponents scoring a game or rubber on the expectation that positive scores on subsequent deals will offset the negative score Owing to the difference in the methods of scoring between duplicate and rubber bridge a sacrifice bid in rubber bridge is much less likely to be advantageous 1 and so strategies differ between the games Comparable strategy differences exist between Matchpoints scoring and IMPs scoring games Contents 1 Scoring context 1 1 Sacrificing against game contracts 1 2 Sacrificing against small slam contracts 1 3 Sacrificing against grand slam contracts 2 Strategy 2 1 Other considerations in sacrifices 3 See also 4 ReferencesScoring context editMain article Bridge scoring Sacrificing against game contracts edit Sacrificing Against a Game Contract Opponents probable game points Our probable penaltypoints in a doubled contractTheirvulnerability Points Tricks down whenwe are vulnerable Tricks down whenwe are not vulnerable1 2 3 1 2 3 4Vulnerable 600 or 620 200 500 800 100 300 500 800Not vulnerable 400 or 420 200 500 800 100 300 500 800In duplicate bridge scoring if the opponents bid and make a game contract it yields them 600 or 620 points when they are vulnerable and 400 or 420 points when they are not vulnerable depending upon the strain and assuming no overtricks Accordingly a sacrifice will be advantageous if the resultant loss in points is less than these amounts Determination of the most number of tricks that can be lost to satisfy this condition is dependent upon the relative vulnerability 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 double the sacrifice bid thereby increasing the penalty points The table at the left summarises the various scenarios and outcomes In summary when the opponents are likely to make a game contract a sacrifice bid which is doubled is viable i e one will still receive a positive relative duplicate score if one can go down no more than three tricks if vulnerability is favourable shown in green two if vulnerability is equal shown in yellow one if vulnerability is unfavourable shown in red Similar reasoning can be drawn for sacrifices against potential slam and partscore contracts and cases where one assumes that the contract will not be doubled Sacrificing against small slam contracts edit Sacrificing Against Small Slam Contracts Opponents expected game points Sacrificer s expected maximumpenalty points and undertricksVulnerability Contract Points Not vulnerable VulnerablePoints Undertricks Points UndertricksNot vulnerable 6NT 990 800 4 800 36 or 6 9806 or 6 920Vulnerable 6NT 1440 1400 6 1400 56 or 6 14306 or 6 1370 1100 5 1100 4When the opponents are likely to make a small slam contract a sacrifice bid which is doubled is viable if one can go down no more than six tricks if relative vulnerability is favourable against a small slam in a major or notrump five tricks if relative vulnerability is favourable against a small slam in a minor five tricks if relative vulnerability is equal where both sides are vulnerable against a small slam in a major or notrump four tricks if relative vulnerability is equal where both sides are vulnerable against a small slam in a minor four tricks if relative vulnerability is equal where both sides are not vulnerable against any small slam three tricks if relative vulnerability is unfavourable against any small slam Sacrificing against grand slam contracts edit Sacrificing Against Grand Slam Contracts Opponents expected game points Sacrificer s expected maximumpenalty points and undertricksVulnerability Contract Points Not vulnerable VulnerablePoints Undertricks Points UndertricksNot vulnerable 7NT 1520 1400 6 1400 57 or 7 15107 or 7 1440Vulnerable 7NT 2220 2000 8 2000 77 or 7 22107 or 7 2140When the opponents are likely to make a grand slam contract a sacrifice bid which is doubled is viable if one can go down no more than eight tricks if vulnerability is favourable seven tricks if both vulnerable six tricks if both not vulnerable five tricks if vulnerability is unfavourable Strategy editA sacrifice most often occurs when both sides have found a fit during bidding eight 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 suit game in advance 8 3 4 Q 10 8 5 4 2 Q J 6 4As 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 three or four against 620 is a 50 50 probability for a top or 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 A 6 K 8 7 4 J 9 7 4 Q J 5 Q 10 8 5 3 NW ES K J 9 7 2 A Q J 6 3 10 5 2 K 8 4 10 9 6 3 2 4 9 5 2 A K Q 10 8 6 3 A 7The bidding starts West North East South1 2 1 2NT 4 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 sacrifice seems to be 4NT rather than 5 it requires a trick less and there is no indication that 5 would provide more tricks than 4NT Indeed 4NT is down one and 5 down two Other considerations in sacrifices edit The scoring matters a lot in sacrifices Matchpoints scoring vs IMP scoring makes a very significant difference in sacrifice decisions Kit Woolsey suggests that the following three conditions should all be met for a sacrifice to make sense in Matchpoint scoring The field is going to bid the game the opponents reached The said game is very likely to make Your doubled sacrifice is likely to not go down too much i e maximum 1 down in unfavorable vul max 2 in equal and max 3 in favorable Slam values are much higher 2 See also editGlossary of contract bridge terms PreemptReferences edit Francis Henry G Truscott Alan F Francis Dorthy A eds 2001 The Official Encyclopedia of Bridge 6th ed Memphis TN American Contract Bridge League p 402 ISBN 0 943855 44 6 OCLC 49606900 Woolsey Kit 2015 Matchpoints 2nd ed Bridge Winners Press p 289 ISBN 978 0 9905229 5 9 Retrieved from https en wikipedia org w index php title Sacrifice bridge amp oldid 1088621666, wikipedia, wiki, book, books, library,

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