Abad retired the first five batters he faced before walking Matt Carpenter. Astros interim manager Tony DeFrancesco and a trainer came out to the mound and made the decision to end Abad's outing.
"He threw the one pitch and I saw him flinching and we went out and checked him and he wasn't ready to go," DeFrancesco said after his team's 6-1 loss.
The trainers told Abad that he would need two to three days to recover.
"I don't feel too much," Abad said. "Just a little bit."
Reliever Fernando Rodriguez went 4 1/3 innings in relief. Rodriguez pitched 3 1/3 scoreless innings on Friday in relief of injured starter Edgar Gonzalez.
Second baseman Marwin Gonzalez was taken out of the game in the fourth inning after spraining his left ankle in the second. It's the same ankle that Gonzalez hurt on Aug. 31. He ended up missing a couple weeks and returned to the lineup on Sept. 20.
In the second inning, Gonzalez singled, moved to second base and couldn't score on a single.
"We were hoping his ankle was going to continue to play and finish the season," DeFrancesco said. "I guess after the base hit he might have aggravated it. I thought on the base hit to right field, he wasn't running well and we weren't able to score him from second base early in the game. At that time, we determined he was better off coming out of the game at that time."