CLEVELAND -- One of their hottest hitters got hurt without even swinging the bat. Their most consistent pitcher had the shortest outing of his career, and the last-place Seattle Mariners spent four days taking batting practice against the Cleveland Indians' worn-out staff.

Frayed all season, the Indians are falling apart.

Felix Hernandez shook off a hard fall on a fielding play to strike out 10, Wily Mo Pena drove in four runs and the Mariners chased Cleveland starter Josh Tomlin before the sixth inning for the first time Wednesday in a 9-2 rout that left the Indians' playoff hopes flickering.

Just 1½ games out of first place less than a week ago, the Indians have lost six of seven and are under .500 for the first time since April 3. They're 6½ games behind the Detroit Tigers in the AL Central.

The race may go on without Cleveland.

"I still feel like we have a good streak in us," manager Manny Acta said, staying positive. "We've still got to play the games. We have to get out there and fight."

The Indians don't have much punch left.

Outfielder Shin-Soo Choo hurt his back on a check swing Tuesday night, and when he reported that it was sore while taking pitches during pregame indoor batting practice, Acta dropped him from Wednesday's starting lineup. Also, catcher Carlos Santana left woozily in the ninth after taking a foul tip off his mask. He was being evaluated for neck pain, Acta said.

Acta has juggled his lineup because of injuries all season, and his batting order included just three players on the field for him on Opening Day.

"You can't sit here and feel sorry for yourself," he said. "It's tough without Brantley and Kipnis and Hafner and Sizemore and now Choo, but you have to continue to play."

Hernandez (12-11) allowed two runs in six innings, and the Mariners, who got 51 hits in four games, became the first team to knock Tomlin (12-7) out before the sixth.

Pena hit a two-run homer in the fourth and his two-run double in the fifth was the final blow for Tomlin, who pitched at least five innings in each of his first 37 career starts. The right-hander and current Toronto Blue Jays manager John Farrell are the only two pitchers since 1919 to begin their careers so consistently.

Mariners rookie Kyle Seager went 4-for-4 with three doubles and batted .769 (10-for-13) in the four-game series. Seattle pitchers combined for 16 strikeouts.

Hernandez's hustle nearly ended his 200th career start early.

In the third, Cleveland's Ezequiel Carrera popped up a bunt to the right side. Hernandez, listed at 6-foot-3 and a generous 225 pounds, made a diving attempt to catch it in the air. He came up a little short, and his fully extended body and head slammed down onto the grass.

Hernandez was dazed as a trainer and Mariners manager Eric Wedge checked on him. The right-hander remained hunched over and seemed unsure before throwing a few warmup pitches and staying in. The Mariners continued to look him over when he came back to the dugout.

"I hit my face," Hernandez said. "I was a little bit woozy, but I was fine after that."

Hernandez scoffed at the suggestion he wouldn't continue.

"No doubt," Hernandez said. "No one was going to take me out of that game."

Tomlin was one strike from owning the record he shares with Farrell when the Mariners got him in the fifth.

He gave up two singles, got two outs and was ahead 1-2 in the count before Miguel Olivo hit an RBI single to snap a 2-2 tie. Seager hit his third double, a ground-rule shot that made it 4-2. Pena, who homered in his previous at-bat, then laced his double to finish Tomlin.

Acta hung his head as he walked to the mound to ask Tomlin for the ball. The right-hander received a warm ovation from Cleveland's fans on his way off.

"It didn't feel good," Tomlin said of his early exit. "You don't want to leave those guys out to dry -- ever. That's the worst fear for me, leaving the bullpen out to dry like that."

The Indians have hardly gone a day without an injury or injury update.

Choo's injury came just as Grady Sizemore was taking batting practice for the first time since July 18. The Indians are also without designated hitter Travis Hafner, who may need season-ending foot surgery. Also, starting second baseman Jason Kipnis and outfielder Michael Brantley are hurt.

It's forced the club to dip into its Triple-A Columbus roster in a playoff chase.

"It's tough and when guys get banged up but part of the game," said third baseman Jack Hannahan, who couldn't remember the last time the Indians were healthy. "It's tough on these guys coming up to be thrown in the fire in a race. It's a lot of pressure."

Game notes

The Indians are off Thursday before opening a three-game series with the Kansas City Royals. ... Sizemore felt "great" following a 15-minute batting practice session, his first since going on the DL in July with a bruised knee and following sports hernia surgery. Sizemore's latest comeback -- he had microfracture surgery last year -- could send him to the minors next week. The Indians hope to have him back by the second week in September. ... Left-hander Anthony Vasquez, who won his major league debut Tuesday, might get another start as Wedge considers a six-man rotation.