ARLINGTON -- Kevin Millwood, on the disabled list with a strained right groin muscle, has been cleared to pitch on medical rehabilitation assignment. He is scheduled to start on Saturday for Double-A Frisco against Northwest Arkansas in a Texas League game.

Millwood is scheduled to pitch approximately five innings and 75 pitches. If that goes well, he could rejoin the Rangers rotation next week either against the Red Sox in Boston or back home against the Rays.

"We're going to get him back in there as quick as we can," Rangers pitching coach Andy Hawkins said.

Millwood threw in the bullpen on Wednesday without problems and was also put through strenuous fielding drills to test his groin muscle. He seemed to pass every test.

"I tried to push it as hard as I could and I didn't feel anything," Millwood said. "Everything went good."

This is the second time that Millwood has been on the disabled list because of a groin injury. He missed more than two weeks in May and did not go on a rehab assignment before he was activated. This time, the Rangers want to make sure he's healthy down the stretch.

"It feels better than the first time," Millwood said. "I've done everything I can to get it well. There's no way to say it's not going to come back, but I think I've done everything I can."

Manager Ron Washington also said that Vicente Padilla is planning to rejoin the team on Friday in Baltimore and pitch on Saturday against the Orioles. He had to return to Nicaragua this week to attend a family matter.