"There were no tweaks or twinges," Hampton said. "The ball was moving, but the location wasn't great. I was just out there to test it, and I got through it and came away without any issues."
Hampton strained his groin on the last pitch he threw on June 12 against the D-backs in Arizona. He was placed on the 15-day disabled list following Houston's 6-1 loss to the Texas Rangers on June 17. The move was retroactive to June 14, and he will be eligible to come off the DL on Monday.
Hampton is 4-5 with a 4.70 ERA in 12 starts this year for the Astros.
"I wasn't really looking at his stuff, but more looking to make sure that he was physically fine," manager Cecil Cooper said. "I know his stuff will be there when he gets on the hill."
Jason Grodsky is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.