Rich Harden was great last night. In seven innings he struck out nine, walked one, and gave up one run while, mercifully, not allowing a home run for only the second time this season. I wanted to see why, so I’m going to step on Harry’s toes here and look at what the Pitch f/x data has to say.

The most obvious reason Harden was so much better last night was his fastball. At an average of 92.74 MPH, it was as fast as it’s been in a few starts. And he threw it for strikes, too: 64 percent of his fastballs were strikes tonight. That’s better than it has been in his past few starts. In fact, here’s what’s been going on with Harden’s fastball over his last three starts:

Last night, then, Harden’s fastball was a bit faster than it had been in his last few starts, and he threw it for more strikes than he had recently. He also threw proportionally more of them than he had been throwing.

It’s tough to say what the reason is — one would hope that it’s more confidence in his ability to blow the fastball by hitters or more confidence in his ability to throw it for strikes. Since he’s only a two-pitch pitcher, one could infer that more fastballs means less confidence in his changeup. But Harden seemed to have a good changeup last night, getting a strike 62% of the time with it.

There’s one other thing I noticed, however — last night, Harden’s best fastballs were in the first couple of innings. He threw four pitches that were at or very close to 96 in the first inning and second innings, then never hit that level again. In his last time out, he touched 96 once, in the fourth inning. The time before that, his high was only 94, and he recorded his best velocities in the second inning.

I don’t know what, if anything, that means, but I wonder if part of it is a matter of establishing the fastball. A hitter who gets a fastball blown by him early in the game, or sees it happen while he’s on deck, may be more vulnerable to the change later, or may just be too amped to make good contact with a slower fastball later on.

Or it may be that when you’re pitching against a team like the PIttsburgh Pirates, if you challenge them with good pitches you’re probably going to do alright for yourself. Harden should start next against the Brewers, so if he has his velocity again, we’ll see how he does against a better offense.