BALTIMORE, Md. -- The Indians left Baltimore with a split in their four-game series with the Orioles. It was not something to rejoice over.

Not only did they lose to the Orioles, 8-3, Sunday, but center fielder Grady Sizemore left the game in the first inning with a bruised right knee. An injury to the same knee in May put him on the disabled list.

Sizemore will accompany the team to Minneapolis, where they play the Twins in a day-night doubleheader on Monday. He'll be examined in Minneapolis and would return to Cleveland if more tests are needed.

The Orioles are struggling, to put it mildly. When the Indians started the series by winning the first two games, they ran Baltimore's losing streak to a season-high nine straight games.

But in losing Saturday, the Indians were beaten by Alfredo Simon, who hadn't pitched more than 4 2/3 innings all season and was making just his second start. It did not stop him from holding the Indians to two runs over seven innings before flying back to the Dominican Republic to face possible charges in a fatal shooting.

The Orioles rolled out rookie right-hander Mitch Atkins on Sunday. Left-handers were hitting .455 (5-for-11) and right-handers were hitting .400 (10-for-25) against Atkins. But the best the Indians could do was three runs in the first inning, highlighted by homers off the bats of Travis Hafner and Carlos Santana. Atkins lasted just three innings, but the Indians didn't score another run against him as they stranded six runners.

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"We started very good offensively, but at the end of the day we left way too many guys on base," said Acta. "We got their starter out of the game by the third inning, but only scored three runs off him.

"We left an army of guys on base and that hurt us at the end."

The Indians stranded 11 runners and went 2-for-8 with runners in scoring position.

It's the first time the Orioles have won consecutive games since June 19-20. The Orioles have lost 23 of their last 31 games.

Following the consecutive homers by Hafner and Santana, Sizemore blooped a hit into short left. As he was rounding first, he pulled up not once, but twice before reaching second with a head-first slide for a double.

Indians lose to Orioles 8-3 6 Gallery: Indians lose to Orioles 8-3

During his slide, Sizemore was hit by left fielder Matt Angle's throw to second. Sizemore came up limping as Acta and trainer Rick Jameyson came out to check on him. After jogging for a bit in center field, Sizemore walked to the dugout and was replaced by pinch-runner Ezequiel Carrera.

Camden Yards has not been kind to Sizemore. Last year, he injured his left knee sliding back into first base in May. He needed microfracture surgery in June and missed the rest of the season. He has been trying to come back from that surgery, along with an injury to his right knee earlier this season, ever since.

"It's the same knee he had the contusion on earlier this season," said Acta. "He made a quick turn around first base and it hurt him so we took him out of the game."

After Sizemore left, Atkins hit Matt LaPorta with a pitch. Travis Buck singled off second baseman Robert Andino's glove to score Carrera for a 3-0 lead. It was the last run the Indians scored.

"When you score early, and give your starting pitcher some breathing room, you think you're going to score more," said Hafner. "We just left too many people on base."

Jeanmar Gomez, activated before the game, couldn't keep the Orioles in the park. He gave up three homers, including a three-run drive to Roberto Andino in the fifth inning to give the Orioles a 4-3 lead.

"He gave up an 0-2 single to Mark Reynolds before the homer and the whole inning escalated from there," said Acta.

Gomez went out for the sixth, but gave up his third and final homer to Nick Markakis before Acta went to the bullpen.

The Indians, trailing 5-3, still had a chance in the seventh. They loaded the bases with one out, but Travis Buck sent a liner back to the mound that hit Jim Johnson in the midsection. Johnson recovered and threw home for the force.

"If that ball goes through, it's a tie game," said Acta.

The Orioles made it 7-3 with two runs in the seventh against Joe Smith, ending his streak of 27 games without allowing an earned run.

The Orioles finished a four-homer day when Frank Herrmann allowed Matt Wieters' blast in the eighth.

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