CINCINNATI - Poor Ken Griffey Jr. He just can't stay healthy.

The 11-time All-Star will miss the rest of the season after rupturing a tendon in his right ankle Thursday night, the latest in a string of major injuries for the Cincinnati center fielder.

''Obviously, it's devastating. It's a shame. He's heartbroken,'' Reds general manager Jim Bowden said in a telephone interview with The Associated Press. ''I talked to Junior earlier, and I told him that we're all praying for him.''

Griffey was hurt while running out a double after pausing at home plate as if he thought his drive to left field would be a home run.

He had to speed up and was hurt just after rounding first in the sixth inning of the Reds' 5-4 home loss to the Houston Astros. The center fielder was scheduled to surgery Friday.

Once thought to be a threat to break Hank Aaron's record of 755 homers, Griffey has dropped from the game's elite because of injuries. He hit .247 with 26 RBIs in 53 games this season.

Griffey had been bothered by a sore tendon for about a week and was getting treatment before games.

Injuries to both legs and his right shoulder have caused Griffey to miss 140 games since the 2000 season, including 33 so far this year.

Earlier Thursday, Reds outfielder Austin Kearns went on the DL, retroactive to July 9, because of an inflamed right rotator cuff, an injury that has bothered him since a May 21 collision at the plate with Atlanta's Ray King.

Cincinnati said it planned to recall right-hander Jose Acevedo and outfielder Ruben Mateo from Triple-A Louisville on Friday. The Reds also scheduled right-hander Scott Sullivan to have an MRI of his sore right shoulder.

''It's tough to take Kearns and Griffey, our 3 and 4 hitters, out of the lineup,'' Bowden said. ''They'd been our two best hitters, but they'd both been playing with injuries all year. Mateo has been playing well. I can tell by all the GMs who have called wanting to trade for him.''

As for the game, Geoff Blum hit a two-run single that capped a five-run second inning for NL Central-leading Houston, which stopped a six-game road losing streak.

Rookie left-hander Jeriome Robertson (9-3) won his fifth consecutive start and eighth straight decision, allowing four runs - three earned - and eight hits in five-plus innings. He hasn't lost in 13 starts since April 25.

Billy Wagner, Houston's sixth pitcher, got three outs for his 25th save in 28 chances.

Paul Wilson (5-7) gave up five runs and seven hits in six innings.

Houston scored a combined 15 runs in the first innings of its previous two games against the Reds, but they waited until the second this time.

Lance Berkman started the second with an infield single that glanced off the inside of Wilson's left foot. Berkman scored on Richard Hidalgos' double. One out later, Everett blooped a run-scoring double down the right-field line, then scored on Robertson's soft single. After Craig Biggio doubled, Blum hit a two-run single.

Larkin and Jose Guillen hit consecutive doubles that scored runs for the Reds in the first and third innings.