Brian Matusz walked into the home clubhouse at Camden Yards on Monday afternoon and smiled broadly when he overheard a conversation about the amateur draft that was set to begin in three hours.

"I remember that day," Matusz said.

With much of the night's focus on whom the Orioles would select with the fourth overall pick in this year's draft, the club's most recent first-round choice to make the big leagues pitched well enough to give his team a chance to win, but his performance did little to squelch persistent questions about his velocity.

In his second big league start this season, Matusz, the fourth overall pick in 2008, allowed two runs over 5 1/3 innings and was backed by a flawless night from the bullpen in the Orioles' 4-2 victory over the reeling Oakland Athletics in front of an announced 10,556, the smallest crowd at Camden Yards this season.

It was the seventh straight loss for the A's (27-34) after they swept a three-game series over the Orioles (27-31) two weekends ago.

"I'm starting to get a little bit more comfortable," said Matusz (1-0), who allowed seven hits, including Adam Rosales' two-run homer in the fourth, and walked two in his second start since missing the first two months of the season with a strained left intercostal muscle. "I'm a little tentative out there and tight, thinking about too many things instead of just relaxing and letting the ball [go]. But I was able to make the pitches today when I needed to.Good curveball working, changeup at times. The most important thing is making good pitches."

Jim Johnson did plenty of that, entering the game with two men on and one out in the sixth and getting Rosales to hit into an inning-ending double play. He pitched a scoreless seventh, and Koji Uehara and Kevin Gregg did the same in the eighth and ninth.