Red Sox second baseman Dustin Pedroia takes a relay from third baseman Mike Lowelll to force out the Orioles’ Aubrey Huff, then fires to first to complete the second-inning double play last night at Fenway Park.

The Providence Journal / Mary Murphy

BOSTON — Bartolo Colon is not an overpowering pitcher anymore.

He’s not terribly tricky, either.

Basically, the rotund right-hander is a two-pitch pitcher, throwing fastballs and sliders.

Since joining the Sox, though, one thing he has been able to do is spot his fastball while keeping hitters honest with a few sliders here and there as well as an occasional changeup.

Last night, Colon’s command of his fastball was so sharp early he could have told the Orioles what was coming and they wouldn’t have been able to square it up because his fastball, thrown anywhere from 88 to 93 mph, had plenty of movement.

Indeed, Colon was virtually telling the Orioles he was going to keep pumping in fastballs, because that’s all they saw over the first three innings. Of his 45 pitches over that stretch, unofficially 40 were fastballs. Baltimore sent 10 batters to the plate against him, managing two hits (there was a double play), and he whiffed four.

Of those four strikeouts, only one — of center fielder Adam Jones — was a function of sliders. The rookie chased one slider, so Colon and catcher Jason Varitek punched him out with a couple more.

As the Orioles’ lineup turned over, though, Colon began mixing in more off-speed pitches.

In the fourth inning, of the 17 pitches he threw, 10 were fastballs, 7 were sliders. He even threw a 2-and-0 slider to Aubrey Huff with a man on first and one out. Huff, no doubt expecting a fastball, popped it up to third baseman Mike Lowell just in front of home plate.

In the fifth, Colon went back to the fastball, allowing a solo homer to Luke Scott on a 92-mph heater. Of his 14 pitches in the inning, 11 were fastballs. He changed his pattern on Jones. Expecting Jones to be looking for the slider, Colon used fastballs exclusively in the four-pitch at-bat, retiring him on a liner to left.

Then, in his sixth and final inning, Colon fired fastball after fastball. He threw 17 pitches in the inning , 14 of them fastballs.

Again, it was his movement on the two-seamer, not so much the velocity, that Colon was making work for him.

With a runner at second, Colon fanned the last two batters he faced. He threw a 90-mph 3-and-2 two-seamer to Huff, the Orioles’ cleanup hitter. The pitch started inside. Huff quit on it, thinking he’d be drawing a walk, and the ball tailed back over the inside corner for a called strike three.

Kevin Millar was next. Millar fouled off the first two fastballs, and then Colon punched him out with a 89-mph fastball. It was another two-seamer, this one starting out over the plate and moving in underneath Millar’s hands. Millar swung and missed.

Colon’s final pitch count was 93, and the unofficial breakdown of his pitches was 75 fastballs, 15 sliders and 3 changeups.

skrasner@projo.com