KISSIMMEE, Fla. -- The topic of possibly having to start the season in the Minor Leagues came up about midway through Brett Wallace's recent interview with a reporter, prompting locker neighbor Michael Bourn -- wrapped in a towel after taking a dip in the hot tub -- to offer his opinion.

"He ain't thinking about that," Bourn said.

Wallace is indeed focused solely on making the roster as the Astros' Opening Day first baseman, but he understands nothing is assured as the team gets ready to begin Grapefruit League play. He still has plenty to prove, and the Astros haven't been shy in saying they have other options if Wallace can't find his stroke at the plate.

This is the stark truth, something Wallace knows all too well and something he's not bashful to talk about despite the urging of his teammate, Bourn.

"My goal here is to work as hard as I can and make the team and help us win," Wallace said. "All I can control is how I prepare and go out and play. I think if I played up to my abilities, we won't have to worry about that."

Wallace, 24, could hold the key to the Astros' season, which certainly comes with a lot of pressure. The fact is, if Wallace can put up the same prolific numbers at the plate as he has throughout his Minor League career, the Astros' lineup becomes deeper, more dangerous and more legitimate.

"As a competitor, you want an opportunity to win the job, and that's what I have," Wallace said. "I think you want to have an opportunity where they're going to have an open mind when you come to camp, and you're going to work for a spot where you think you can help the team. You kind of expect yourself to go out there and play well, and any extra stuff on the outside doesn't affect you at all."

After getting traded in July to the Astros from the Blue Jays in an offshoot trade of the deal that sent Roy Oswalt to the Phillies, Wallace was thrown into the starting lineup to replace franchise icon Lance Berkman, who was dealt to the Yankees. He went from a Minor League first baseman with the Jays to Major League starter with a new organization in a dizzying 48 hours.

Wallace hit .222 with two homers and 13 RBIs in 144 at-bats in his first Major League season, after batting .301 with 18 homers and 61 RBIs in 2010 at Triple-A Las Vegas. A first-round pick of the Cardinals in '08, he's a career .304 hitter with 46 homers and 160 RBIs in 287 Minor League games.

"The experience he got last year at the Major League level was huge for him," Astros manager Brad Mills said. "There's been all kinds of talk about how he's been traded and in big deals and really hasn't had a chance to get situated with an organization, but he was able to get experience last year and find out what it's about."

The Astros had flirted with signing a left fielder in free agency this winter, in case Wallace had to start the season in the Minors and left fielder Carlos Lee had to move to first, but the club had a change of heart after deciding that might put too much pressure on Wallace.

"To me, the perfect-world scenario was that Brett Wallace comes in and wins the first-base job and is our guy, and Carlos is the everyday left fielder and we're not worried about mixing and matching in left with Carlos at first, or trying to push [Brian] Bogusevic harder to play more," general manager Ed Wade said. "I know we're going to get Brett every opportunity to win that job, [but] a lot of things will get answered if indeed he does step up and does that."

Wallace is doing everything he can to ensure he wins the job. He came to Houston shortly after the start of the year and was a regular at Minute Maid Park, working out with strength and conditioning coach Gene Coleman. He reduced his body fat and added some muscle, though his stocky frame hasn't changed much to the untrained eye.

"I wanted to be prepared physically, but also show the team I was going to be ready to go when Spring Training started, and I thought it was a good opportunity to be out in the community and get a chance to actually be part of Houston and get to know my teammates like C.J. [Chris Johnson], Bogi [Bogusevic] and all those guys," Wallace said. "It's just a good opportunity to kind of get a chance to grow with them a little more."

Wallace is focusing on trusting his hands more this year and staying back in the box to see pitches longer. He's confident he can reward the Astros for their faith in him and sure he can hit Major League pitching.

"I think as a competitor you have to believe that," he said. "I think the biggest thing is you try to force things early. Last year, let me get my feet wet and get comfortable, and coming into this year I'm excited about the work we've done in the offseason, and I'm excited to get out there and try to get back on track."

When asked what he would have to do this spring to make the club, Wallace said the proof isn't going to be in statistics.

"It's more about the way I go out there and take care of my business and work hard and mesh with the team and try to help the team win," he said. "I don't think it's about numbers and things like that, but we want to win as many games as we can, and if I can show them different ways I can help the team win, that's going to force their hand a little bit."