Safety play

Safety play in contract bridge is a generic name for plays in which declarer maximizes the chances for fulfilling the contract (or achieving a certain score) by ignoring a chance for a higher score. Declarer uses safety plays to cope with potentially unfavorable layouts of the opponent's cards. In so doing, declarer attempts to ensure the contract even in worst-case scenarios, by giving up the possibility of overtricks.

Safety plays adapt declarer's strategy to the scoring system. In IMP-scoring tournaments and rubber bridge, the primary concern is to fulfill the contract, because overtricks are of secondary interest. Therefore, safety plays are an important part of declarer technique at quantitative scoring.

In matchpoint games, which use comparative scoring, overtricks are very important. Therefore, although safety plays have a certain role at matchpoints, they are normally avoided if the odds for making the contract are good and overtricks are likely.

Definition

The term "safety play" is difficult to define crisply. The Bridge World glossary [ [http://www.bridgeworld.com/default.asp?d=bridge_glossary&f=glossa.html The Bridge World glossary] ] defines safety play as "the surest line to make the contract, disregarding extra tricks that might be made in some other way." Marshall Miles [Miles, Marshall. How to Win at Duplicate Bridge. Collier, 1957.] has defined it as "playing in such a way as to lose a trick with average breaks in order to avoid losing additional tricks with bad breaks."

Conflating discussions from various sources yields the following points, each descriptive of safety play characteristics:

*A safety play is made in a single suit. In the context of that suit, it can often be described using other terms that might or might not pertain to the full deal, such as avoidance play, percentage play, coup or duck.

*A safety play, although made in a single suit, is intended to maximize declarer's chances to make the contract.

*A safety play usually gives up the opportunity to win as many tricks as possible in a particular suit in order to gain an advantage on the full deal. It therefore is sometimes compared to an "insurance premium".

Examples

Safety plays have a role at both comparative scoring and quantitative scoring, although they are used more often at quantitative scoring because they tend to give up on overtricks.

afety play at IMPs

This hand [Kelsey, H.W. Test Your Match Play. Faber, 1977.] is from a team of four game:

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

South plays 6NT against the lead of the Spades10. Dummy's SpadesK wins, and the ClubsA and ClubsK are played. East discards a small spade on the second club trick.

This particular hand is one of a relatively small group of (non-trivial) deals in which perfect safety is available after the third trick. Single-dummy, using a safety play in diamonds, it is possible to guarantee the contract against any remaining distribution and play of the E-W cards.

South started by expecting to win five clubs, one or two diamonds, four hearts and two spades, but the 4-1 split in clubs complicates matters. Still, a safety play in diamonds will bring in twelve tricks.

It's just coincidence, but the proper diamond play on this hand is the same as the percentage play with this diamond holding, considering the suit in isolation. The best play for three diamond tricks is to play the DiamsA, and then lead toward either the DiamsQ or the DiamsJ. This play brings in three diamond tricks 73% of the time.

Using that play on this deal brings in twelve tricks 100% of the time. Cash the DiamsA, and lead small toward the DiamsQ. Then:

*If diamonds are 3-2, South will always win three clubs, three diamonds, four hearts and two spades.
*If diamonds are 4-1 and West has the singleton, East cannot play the DiamsK on the second lead without setting up both the DiamsQ and the DiamsJ. If East plays low and West shows out, concede a club and take four clubs, two diamonds, four hearts and two spades.
*If diamonds are 4-1 and East has the singleton, West can capture the DiamsQ with the DiamsK. But in that case West is known to hold four cards in each minor, and on the run of the major suits will be squeezed out of his guard in either diamonds or clubs. In with the DiamsK, West can attack dummy's entry in diamonds or in clubs, but not both.

afety play at matchpoints

Safety play usually involves giving up the chance of the maximum result in exchange for the best chance of making the contract. So one seldom sees safety plays made at matchpoints or board-a-match. But even at those forms of scoring, there can be good reasons to make safety plays.

Suppose that, at pairs, declarer is in a standard contract, one that the majority of the field will surely reach. However, the defense makes an unorthodox opening lead, presenting declarer with a possible overtrick. There may now be a way, unavailable to other declarers, that will guarantee the contract while retaining good chances for the overtrick.

Or declarer might be in an unusually good contract. Hugh Kelsey [Kelsey, H.W. Match-Point Bridge. Faber, 1970.] gives this example:

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

The bidding goes 1Hearts – 2Hearts; Pass, and West leads the SpadesK and continues with the Hearts10.

South is in an unusually good matchpoint contract. Most players will open the South hand with 1NT rather than 1Hearts. And it is very difficult to reach a heart contract if South opens 1NT or 1Diams: either way, North signs off in diamonds.

In any case, 2Hearts is both an exceptionally good matchpoint contract and difficult to reach. Assuming reasonably competent defense, plus 130 is the limit playing in diamonds, and plus 120 in notrump contracts.

But there's an easy way to score plus 140 in 2Hearts: take a safety play in hearts by ducking the first round. This gives up the chance of plus 170 (if hearts break 3-3) in exchange for the best chance of plus 140 (if hearts break either 4-2 or 3-3). Note that playing hearts from the top leads to defeat if hearts are 4-2, the most likely split.

afety play at notrump

Safety plays, of course, are not limited to trump contracts. Here is an example of a safety play at notrump.BridgeHandNS
A 10 8 7 2|A|A 5 3 2|8 4 3
K 9|K 10 2|K 9 6 4|A K 6 2South declares 3NT and gets the lead of the HeartsQ. After winning the HeartsA, declarer leads the Spades2 and East plays a small spade. The play of the Spades9 now assures the contract.

If West wins the trick he cannot play another heart without giving the ninth trick to declarer and the tempo to develop more in spades. West therefore switches to a diamond and South wins in hand. South overtakes the SpadesK with the SpadesA – the key play on this hand – and the DiamsA assures an entry to two more spade tricks. If spades are played from top the hand might not make if East holds Q J x x and both minor suits fail to break.

ee also

*Scoring and tactics in duplicate bridge
*Loser on loser
*Holdup (bridge)
*Avoidance play
*Suit combinations
*Belladonna coup

References