The 37-year-old had signed a Minor League contract in January with a clause that allows him to opt out if he has not been assured a Major League roster spot by March 25.
"Like I said the first day of Spring Training, I don't take anything for granted," Garcia said. "I come here and do my stuff and work hard and try to do my job the best I can. Too bad a couple guys went down. You don't want to see that, but it's baseball. It happens. You've got to move on and continue to play."
On Thursday afternoon in an 11-0 loss to the Cardinals, Garcia allowed four runs -- three earned -- on six hits with three strikeouts and a walk in four innings.
Matt Holliday and Yadier Molina both hit RBI doubles in the first. In the second, St. Louis scored an unearned run without a hit. Mark Ellis reached on a fielding error by Tommy La Stella and stole second on Peter Bourjos' strikeout swinging. He advanced to third on Stephen Piscotty's flyout to right and came home on Garcia's wild pitch to Matt Carpenter.
It looked like Garcia would escape damage in the third when he induced a 4-6-3 double play from Molina, but Jhonny Peralta doubled on the first pitch. The ball, affected by 17-mph winds, seemed to give Justin Upton trouble in left. Garcia responded with a clean fourth.
Of his 73 pitches, 44 went for strikes.
"It's hard to pitch like this in this kind of weather," said Garcia, whose pitches ranged from the 70s to mid-80s. "No excuse, but my ball is moving all over the place. For me, I have to throw first-pitch strikes, and in the last couple of innings, I wasn't able to do that.
"I have to be ahead all the time. At this point, I won't be able to do 2-1, 3-1. I have to be ahead pretty much. I tried to do that, but it happens."
After opening Grapefruit League action with five scoreless innings in his first two outings, Garcia has surrendered 10 runs -- nine earned -- on 12 hits with five walks and five strikeouts.
Last Saturday, Garcia learned his wife was going into labor with their third child before pitching against the Marlins. After giving up six runs with four walks in 2 2/3 innings, he drove to Miami for his son's birth.
"I feel pretty good," said Garcia, whose family watched him pitch on Thursday. "I give up a lot of runs lately, but I'm fine. It's different when the bell rings. Spring Training games are different. I just need to pitch better next couple of starts."
Before spring began, Garcia didn't care whether he was used as a starter or reliever so long as the appearances meant he'd be back in the Majors.
The 15-year veteran holds a career 156-108 record and 4.15 ERA. He has thrown 200-plus innings seven times in his career, but not since 2006.
"He's a veteran professional guy," manager Fredi Gonzalez said. "He was a late addition to Spring Training, really, and we wanted to get some depth. I think he's a little more valuable than depth right now. He's a guy that's going to be in the rotation. He's going to be really, really valuable to us."
When the Orioles took Garcia off their 40-man roster last June, the Braves traded for him two months later. He went 1-2 with a 1.65 ERA in six games (three starts). Over 27 1/3 innings, he gave up five runs and five walks, while striking out 20.
Garcia was in line for the win in Game 4 of the National League Division Series at Dodger Stadium after tossing six innings of two-run ball.
"Whatever they need me to do, I'll be there," Garcia said. "I know when the season starts if I make the team I can pitch a lot of innings, do a lot of things. Hopefully if I can make the team and move on, go from there."
Christina De Nicola is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.