Lohse, who threw two innings to hitters Troy Glaus and Rick Ankiel, will initially work out of the bullpen until his spot opens up in the rotation. He was placed on the DL on August 22 with a strained left groin.
"I got done what I wanted to get done," Lohse said. "I didn't feel anything so as soon as I am eligible, we'll rock and roll.
"The first 20 pitches or so were decent, I was more concerned with how the ball was coming out more than anything and it felt lively. The second set I thought was better execution and stuff. It's always tough with the cage and guys behind there and you don't want to hit your own guys when you are coming inside so you're going to be a little careful and not handle it exactly like a game situation."
Lohse walked two hitters but didn't give up much solid contact to Glaus and Ankiel, who each took four at-bats against him.
The righty signed a four-year $41 million contract extension last September but has struggled to stay on the field. He's battled a series of injuries to his forearm, knee, back and now his groin, among other things.
Pitching out of the bullpen will do nothing but add to the weirdness of the 2009 season for Lohse, who is 5-8 with a 4.67 ERA.
"Whatever the team needs," Lohse said. "I'd love to go out there and finish the way I started, but we got four guys who are going good right now and a lot of off-days. It's unfortunate for myself but its good on the other hand that we don't need to rush me back out and start. I'll do whatever the team needs and see how it goes.
"It's getting tiring. I'm tired of watching and not being involved. It's making it easier with how the team is doing but personally I want to get back out there and compete."
B.J. Rains is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.