CLEVELAND - Bud Norris stayed unbeaten with Baltimore and Nate McLouth homered and had three RBIs, leading the Orioles to a 7-2 win over the reeling Cleveland Indians on Monday night in a matchup of two teams scrapping for an AL wild-card berth.
Norris (10-10) allowed one run -- a homer to Jason Kipnis -- and four hits in seven innings. The right-hander improved to 4-0 with the Orioles, who acquired him at the July 31 trading deadline from Houston.
Matt Wieters hit a two-run homer in the ninth and Brian Roberts drove in two runs for the Orioles, who came in three games behind Oakland and Tampa By in the wild-card race.
The Indians lost for the sixth time in seven games and could be without All-Star Justin Masterson (14-10) for the most important stretch of their season. Masterson left in the second with what the team said is "soreness" in his rib area.
After dropping two of three in Boston and New York, the Orioles, who staggered through a 12-14 August, arrived in Cleveland needing to string some wins together.
"I knew that schedule was going to be a challenge," manager Buck Showalter said before the game. "We're .500 in our last 10 games. Is it half full or half empty?"
Norris provided some more optimism, striking out eight and keeping his record unblemished in seven starts since joining Baltimore. He allowed just one hit through five innings, and picked Michael Brantley off second in the second.
The Indians are sliding in the wrong direction.
They went 1-5 on a trip to Atlanta and Detroit, only salvaging the finale Sunday thanks to a ninth-inning grand slam by Mike Aviles to beat the Tigers.
Masterson initially showed discomfort while working to Wieters leading off the second. Cleveland's top starter grimaced and flared his elbow at his side, a motion that sent Francona to the mound accompanied by a trainer.
The right-hander stayed in the game, but after allowing a single to Wieters, he threw an 87 mph fastball to Nick Markakis and paused.
Shortstop Asdrubal Cabrera went to check on his teammate and immediately waved toward the dugout, bringing Francona again. He took the ball from Masterson, who dejectedly walked off the field and then disgustedly tossed a cup of water in the dugout before heading to the clubhouse.
The loss of Masterson for any amount of time would be a major blow to the Indians and their postseason chances. He's their unquestioned ace, leading the team in wins (14) and innings (190 1-3), and the 28-year-old is tied for the league lead with three shutouts.
Preston Guilmet replaced Masterson and gave up a single to Markakis. With one out, McLouth hit an apparent RBI double to center. However, the Indians won an appeal that Markakis missed second base, and under rule 10.05, McLouth was not awarded a hit on the play because it was a forceout.
After Guilmet walked No. 9 hitter Alexi Casilla, Roberts hit a two-run double to make it 3-0.
McLouth's 10th homer put the Orioles ahead 5-0 in the fourth. J.J. Hardy singled with one out before McLouth pulled a pitch from Nick Hagadone over the wall in right.
Lonnie Chisenhall homered in the eighth off Tommy Hunter for Cleveland's other run.
NOTES: Indians RHP Corey Kluber, sidelined since Aug. 6 with a sprained middle finger, will pitch in relief Friday after Scott Kazmir starts against the Mets. Kluber pitched a simulated game Monday, and because he hasn't pitched in some time, the Indians want to be conservative with him. Also, the club is concerned about overworking Kazmir. "I think it has a chance to help us win, help both pitchers and help the bullpen," Francona said. ... Orioles LHP Zach Britton was recalled from Triple-A Norfolk. He's 2-3 with a 4.76 ERA in six starts for Baltimore this season. Britton will be used in the bullpen for now. ... Indians OF Ryan Raburn is expected to be activated Tuesday after being sidelined with a pulled calf muscle. ... With his next homer, Hardy will become the fourth active shortstop and ninth since 1901 to record three or more seasons with 25 or more homers.