MILWAUKEE -- Nursing a tender left shoulder and dealing with a pair of aging knees, left-hander Mike Hampton will miss his next turn in the rotation, originally scheduled for Wednesday against the Marlins.

Astros manager Cecil Cooper said Sunday that Hampton likely won't start until next weekend, but more will be known after Hampton throws in the bullpen Tuesday at Minute Maid Park. Hampton left Thursday's 9-2 loss at Florida after five innings with a strained shoulder.

"He threw a little bit [Saturday] and he's going to throw an aggressive-type 'pen [session] on Tuesday, and after that we'll make a determination on whether he can throw or not," Cooper said. "If he's OK, we'll slide him in probably Saturday. We'll have to wait until Tuesday and see."

Hampton, 36, left his Aug. 8 start after two innings with a knee sprain, and was later diagnosed with a torn lateral meniscus in his right knee after undergoing MRIs on both knees and receiving cortisone injections. He played light catch Saturday and took Sunday off.

Hampton is 7-10 with a 5.30 ERA in 21 starts this year.

"He'll throw Tuesday, and we'll see how he projects from there," Astros pitching coach Dewey Robinson said. "For me, that's going to be a test to see how he feels and how his knees and everything else feel, and we'll plan out from that."

Because of Monday's off-day, left-hander Wandy Rodriguez could pitch Wednesday on his normal amount of rest.