The Seattle Mariners went into spring training this past March with a new mantra from their pitching coaches: "Pitch to contact." They apparently had t-shirts made up, which, in case you were never in Glee Club in college and don't know this, is completely cheesy. The antithetical philosophy would be to try and strike out every batter a pitcher faces, and this indeed has some drawbacks--trying to strike a batter out in baseball will generally require more pitches, whereas if the batter puts the ball in play, he could conceivably get himself out with one pitch. Moreover, a strikeout pitcher might try to throw more finesse pitches that are harder to locate, and end up walking a lot of batsmen, which puts him in trouble in an inning, and forces him to throw a lot of so-called "stress pitches." A pitcher who racks up higher pitch counts will get tired sooner in the game, and so on and so forth.
There's also (seemingly) a statistical basis for this philosophy, too. Statistical analysis has shown that once a batter has put a pitched ball in play, the pitcher has little to no control over whether it becomes a hit or not. There's a statistic called Batting Average on Balls In Play which measures how successful batters are at reaching base safely once they've hit a pitch (assuming that it doesn't go over the fence for a home run, in which case there's usually nothing the defense can do). This number tends to sit in a range centering around about 30%, but has very little correlation from pitcher to pitcher and year to year--if a pitcher has a .280 BABIP one year, it's as likely to be .330 as .280 the next season (knuckleballer pitchers, such as Boston Red Sock Tim Wakefield, tend to be the exception to this rule of seasonal correlation, but that's another story). Sometimes a ground ball gets through the infield for a single and sometimes the shortstop gets it for an easy out, and this outcome has little to do with the pitcher and a lot to do with a) how much ground the defense behind him covers, and b) luck . So if a coaching staff knew (or thought) they had a good defensive team, pitching to contact would appear to make a lot of sense.
The Mariners apparently have a lot of written or unwritten philosophies like this. They coach their hitters to be aggressive, and look for a good pitch to hit early in the count. They also toyed, more last season than this, with being aggressive once they got on base, trying to go from first to third on a single, for instance.
In tonight's game, in the top of the first inning, Vladimir Guerrero came to bat against Mariner pitcher Jarrod Washburn with a runner on first base. Here is the book on pitching to Vladimir Guerrero: Under no circumstances should you pitch to Vladimir Guerrero. He can hit pretty much any pitch anywhere near the plate and hit it very hard. He is an extremely good hitter. If you were to, for some reason, ignore this information, and throw him hittable pitches, he would hit them. Hard. Pitching to contact against Vladimir Guerrero is a bad idea. It is bad. Bad. Bad bad bad. A better strategy would be to throw unhittable pitches far out of the strike zone and hope he swings at them or just walk him than, rather let him beat you with his bat. Vladimir Guerrero took the very hittable pitch he was thrown and deposited it into the left field bullpen for a home run. Later in the game he came to bat with another runner on and doubled, Mariner pitchers apparently being unable to parse blatant object lessons.
Jarrod Washburn was doing pretty well so far this season: he'd managed to win more games than he lost while sporting a very good earned run average for the most part by throwing strikes and letting hitters get themselves out. By coincidence, Jarrod Washburn had also been facing some baseball teams with pretty poor lineups. But throwing hittable pitches to batters who are good at hitting hittable pitches is highly likely to eventually result in bad outcomes. Similarly, when the Mariners tried to always take that extra base, it worked some of the time, and some of the time the ball wasn't hit far enough or they were facing a team with canon-armed outfielders and they just ran themselves into outs. As for their "aggressive" approach to hitting, when the Mariners face pitchers who tend to throw strikes early in the count, they tend to do pretty well. When they face pitchers who aren't as good, who have trouble hitting the strike zone with regularity, they tend to do poorly--they frequently get absolutely stymied by pitchers who have just come up from AAA, going up hacking at the first pitch that looks hittable instead of letting the pitcher get himself into trouble by walking batters and running up his pitch count...sounds a little bit familiar, doesn't it? Seems like there's some sort of object lesson there.