BALTIMORE -- Even though A's reliever Ryan Cook doesn't consider himself to be a power pitcher, he accomplished a rare feat Friday night against Baltimore: striking out four batters in the eighth inning in Oakland's 5-2 victory.

Cook joined Blake Stein (1998) and Erik Hiljus (2001) as the only A's pitchers to strike out that many batters in one inning. Overall, it was the 59th time that has happened in the history of Major League Baseball, including the postseason. The Astros' Bud Norris accomplished the feat on Tuesday against the Brewers.

"It's not something that's really your goal when you go out there," Cook said. "Once I got [Matt] Wieters out, I realized it. Of course, it's neat. I've never done that before. Like I said, it's not something you're trying to do."

Cook opened the inning by striking out J.J. Hardy, Nick Markakis and then Adam Jones. However, his final pitch to Jones got by catcher Kurt Suzuki, allowing Jones to scamper to first. Cook then struck out Wieters swinging, putting his name in the history books. Cook said he used fastballs and sliders to get the outs

"I've really been struggling with the slider as of late," Cook said. "It's been constant work every day to get my slider back. It's kind of always been my strikeout pitch, and I haven't had it all year. So tonight, it was better."

Along with starter Brandon McCarthy's strong outing, the A's improved to 11-10 and are above .500 for the first time since last May. Even the Orioles were impressed by Cook's performance.

"I was glad to be a part of that," Jones said. "That happens, you know what I mean. It doesn't happen often, but it happens. You just try not to be part of it again."

A's manager Bob Melvin could not recall if he had ever been part of a game when the pitcher struck out four batters in one inning.

"You don't see that often," Melvin said. "It is a rarity. I want to say I've seen it, but I can't think of any offhand."