One of the big differences between matchpoint pairs and IMP team scoring is the importance of sacrifice bids. Team players are more hesitant to sacrifice because the profits are often small (minus 500 instead of 620) and being wrong can be so costly.
Sacrifices are more common in pair events, where small savings can be worth lots of matchpoints. They also create tougher dilemmas for your opponents. When you outbid them at IMPs, they're more likely to double and take the sure plus. At matchpoints, though, there's more pressure to go for the optimum score. If you can safely force them into making a bid-or-double decision, they'll sometimes get it wrong.
Your opponents would usually prefer that you stay silent and let them play at the level they choose, but there are many exceptions. These include auctions where you're doing the guessing instead of them. That's often the case when you make a solo sacrifice (discussed in the previous issue) after they've already exchanged information.
The most welcome competition of all is the phantom sacrifice, where you find out -- too late -- that their game would have gone down. Even if you incur a relatively small penalty, the scoring swing can be huge because you've turned a plus score into a minus.
So how do you determine if the opponents can make a game? It's not an exact science. Success in judging these situations comes with experience, but there are a number of clues that can help you make better decisions.
In general: If you have doubts about the success of their game or the safety of your sacrifice, pass and go for the possible plus score. Here are some of the conditions that should create those doubts:
You have low honors outside your trump suit. Queens and jacks in shorter suits are dubious values for offense, but can be important tricks on defense, especially when the opponents have shown relatively balanced hands.
You have zero, two or four cards in their trump suit. Even a weak four-card holding may be a defensive asset, and unless their auction has shown a giant fit, a void hints that partner has trump length and perhaps strength. A doubleton trump is harder to evaluate. It bodes well for the opponents' contract (their suit is breaking), but not for your sacrifice because of the likelihood of two quick losers in their suit. A doubleton is also a "wasted" ruffing value if partner has shortness.
You have a good (attacking) opening lead -- or you expect partner to have one.
The opponents have "crawled" into game (with an invitational auction) or one bidder has shown weakness (by preempting, rejecting a game try or passing his partner's opening bid).
You've pushed them into game. There are few results more demoralizing than going down 500 or 800 when you could have passed at your previous turn and collected 100 -- or never bid at all and given up only 140.
The vulnerability is equal or unfavorable. Unless you're white vs. red, your high-level sacrifice usually won't give the opponents too much of a problem. At other vulnerabilities, they'll almost always double rather than gamble on a minus score.
Your sacrifice is at the five-level. A phantom 4S sacrifice will occasionally induce the opponents to bid too high, but don't expect them to take the bait over a five-level save. Even red-vs.-not at matchpoints, opponents are reluctant to be pushed into five-over-five contracts, so you'll want to be sure that your hand and the conditions are near-perfect.
The auction hasn't given you a clear picture of partner's values. Don't make a blind guess. Mumble "Get fixed, stay fixed" to yourself and let the opponents have the contract.
© 2013 Karen Walker