Thanks to Lou Piniella’s advice or to Milton Bradley’s borrowed bat, Ryan Theriot has managed to show a little power this season. Unquestionably, that’s changed him. My only concern is that it hasn’t changed him enough.

Alfonso Soriano led off the fifth inning of yesterday’s game with a double. The Cubs were unable to get him home, though — Theriot sacrificed him over to third, and then Milton Bradley flied out, but not deep enough to score, and Derrek Lee grounded out to end the scoring chance. The Cubs would have been in a better position to win the game if Theriot had just swung away.

It’s a little cliche to say that the out is the most precious resource in baseball, but it’s still true. You only get 27 outs in a game, and you only get three before you have to let the other team bat again. There are very few times when you should give one away, and a man on second with no outs is definitely not one.

Consider what could have happened in that inning after the Soriano double. He’s reasonably fast, and he’s on second base. There’s no threat of a double play. A single probably scores him and at least gets him to second. A deep fly or a groundout to the right side might move him to third. If Theriot strikes out or fails to advance him, the Cubs are in that same position when Bradley comes up. But if Theriot gets on base, the Cubs are in even better position.

Now consider what could have happened after Theriot’s sacrifice. Soriano is on third with one out. A hit definitely scores him. Many, but not all, fly balls and some groundouts would score him. A wild pitch or a passed ball scores him, but those aren’t very common. And now the Cubs only have two batters to get him home. One of those batters is hitting in the low .200s, and the other hasn’t played in several days. So the Cubs have slightly more ways they can score Soriano, but they’ve passed on one of just three chances they had to do so.

In fact, if you look at the numbers, Theriot’s play was a bad one. According to Fangraphs’ gamelog, the Cubs’ odds of winning the game went from 76.6 percent before the sacrifice to 75.6 percent after. By sacrificing, Theriot actually hurt the team. Another way to look at it is how many runs you can expect from the situation. From 1999-2002, teams with a man on second and no outs scored an average of 1.189 runs in that inning. After the sacrifice, the Cubs had a man on third with one out — teams in that situation averaged only .983 runs.

Those numbers don’t take into account the batter in question, though. If a batter is a really bad hitter, maybe taking the bat out of his hands isn’t a bad idea, even if it means he’s not likely to reach base, or drive in the runner himself. When Ryan Dempster, for example, lays down a sacrifice bunt, I don’t mind it. But that’s because Dempster is not a good hitter, and he was very unlikely to get on base or to get the runner home himself, so at least the Cubs got something out of his at bat.

Theriot, meanwhile, isn’t really a terrible hitter. A lot of Cubs fans overrate his hitting ability, but he’s not bad, and this season he’s actually been pretty good — even though he’s getting on base less, his ability to drive the ball has been useful. He could do something good with the bat in his hands, and it doesn’t make sense for him to give himself up.

Baseball is a somewhat unique sport in that fans praise players for being “unselfish” when they try to “manufacture runs” instead of trying to get on base. I think maybe a useful analogy would be to basketball. When a player has an open shot near the basket, a good player won’t dish the ball out to the perimeter, he’ll take the open shot. That’s what a man on second with no outs is — it’s an open shot. Relying on your teammates to get it done is great, but if you have a good chance of helping your team yourself, it doesn’t make sense to pass on an opportunity. A decent hitter laying down a sacrifice isn’t unselfish; it’s just unnecessary.