HOUSTON -- If you watched Kyle Schwarber on Thursday night, he was sticking his right leg out when he was behind the plate. Remember, he had surgery on his left knee to repair two torn ligaments, and this spring, he's been extending the left leg.

"We changed it for spring to give [the knee] time to get the complete healing," Schwarber said Friday. "They say it takes 12 months to be completely fine. When I catch, I'd rather be bending down on my left knee. I'll switch it up here and there. I'm mostly going to stay on my left."

It's a good sign that Schwarber's left knee is strong enough that he can do that, considering it was uncertain whether he'd catch again after the injury, sustained in the third game of the regular season last year.

"Everything's good," Schwarber said.

Schwarber caught four innings in a Minor League game one week ago in Arizona, and he switched from left field to catcher in the sixth inning on Thursday against the Astros in an exhibition game at Minute Maid Park.

"It was a good little tuneup," Schwarber said about Thursday's game. "Overall, I thought it was a good day for my second day back there in a live game, especially in a big league game. There were a lot of positives there. I made all the blocks, made a good throw down to second. I thought overall, I want to eliminate the mistakes, but it was a good day."

Schwarber was charged with a passed ball in the sixth, which allowed a run to score, but he also threw Marwin Gonzalez out at second.

"They kept running off me -- I said, 'Geez, take it easy, guys. It's the second game,'" Schwarber said, laughing.

Whenever he had an off-day in Spring Training, Schwarber would catch a bullpen session and do early work with the catchers.

"Once I started to ramp up for the Minor League game, I'd start doing some blocking and getting back on my left knee to make sure it was fine," Schwarber said. "[Thursday] was that last mental hurdle to know I can do it still in the big leagues."

The Cubs' new leadoff man, Schwarber and manager Joe Maddon have come up with their own message before each of his at-bats. Last year, Maddon would tell William Fowler , "You go, we go." On Thursday, Maddon wouldn't reveal what he'll say to Schwarber, saying it was "X-rated." Schwarber wouldn't reveal it, either.

"No messages," Schwarber said. "It's going to stay secret on my end."

Carrie Muskat has covered the Cubs since 1987, and for MLB.com since 2001. She writes a blog, Muskat Ramblings. You can follow her on Twitter @CarrieMuskat and listen to her podcast.