Much of it was painful and frustrating.
Now, after overcoming surgeries to both knees, the 6-foot-2 native of Michoacan, Mexico, will be standing tall on the mound on Wednesday afternoon in Game 1 of the National League Division Series against the Phillies.
Playoff pressure might make some young players nervous. Not Gallardo, who has earned the confidence of his organization and teammates with his composure and competitiveness.
"He's a special young man," Brewers manager Dale Sveum said. "He's got the heart of a lion, and that's pretty much based on why we're starting him.
"Obviously, he's put himself through a lot this season with the knee injuries, and he battled back and did everything he could. He threw four great innings against the Pirates a week ago. And his makeup, we feel he's really the right guy for Game 1."
Wednesday will be the first playoff game for the Brewers since Game 7 of the 1982 World Series.
Born in 1986, Gallardo is up for the challenge, armed with 24 total innings pitched and unwavering confidence.
"I try not to show too much emotion out on the mound, whether it be good or bad," Gallardo said. "It's the postseason. I'm sure there's going to be something there [Wednesday]. We'll see how it plays out."
Gallardo went a long time between starts -- from May 1 to Sept. 25, when he tossed 67 pitches over four innings in a no-decision against the Pirates. He added seven strikeouts.
"He's got the complete package," Sveum said. "He's got the changeup and the curveball, and the heavy fastball. He has the extra velocity when he needs it."
Veteran Jason Kendall caught Gallardo's return against Pirates.
"I told him that day, 'You should be proud of yourself, regardless of the outcome,'" Kendall said. "The fact that he had that type of serious surgery, to come back four months later, that's pretty special. His stuff was definitely there -- the same as where he left off [in May]. That's what was so impressive. I know he had been working, but there's a big difference between 'sim' games and actually being out there."
The low-key Brewers player has ringing endorsements to face a daunting Phillies lineup, which features speed and power, not to mention lefty slugger Ryan Howard. On top of dealing with an imposing opponent, Gallardo will be center stage in front of a hostile, sellout crowd at Citizens Bank Park.
"'Yo' is unbelievable, man," said Brewers ace CC Sabathia, who will start Game 2 on Thursday. "He's not a normal 22-year-old. I think a lot of people in here wish they could be as calm as he is. I think that's what makes him special. If he comes and asks me, I'll talk to him about it."
Sabathia understands the trials presented with pitching as a rookie in the playoffs. The lefty did so in 2001 when he was with the Indians.
"He's got that something about him that he doesn't get rattled. I think he's the perfect guy to start Game 1."
In the best-of-five NLDS, the Brewers have announced that Gallardo and Sabathia are lined up for the first two games. The team will announce who will go in Game 3 on Friday in Milwaukee. It appears to be Dave Bush. Jeff Suppan said before Tuesday's workout at Citizens Bank Park that he will start Game 4, if necessary.
The regular season was projected to be a breakout season for Gallardo. He entered Spring Training on pretty even footing with Ben Sheets for the title of staff "ace." It didn't pan out that way, as he was bothered by a sore left knee. He underwent surgery on Feb. 19 to repair torn cartilage. Eight days later, he turned 22.
Gallardo's 2008 debut was on April 20, when he made his first start, but his rotation stint didn't last long. At Wrigley Field on May 1, Gallardo severely damaged his right knee while covering first base on Cubs outfielder Reed Johnson's slow roller to first base.
The injury occurred when he attempted to hurdle Johnson, but ended up colliding. An MRI revealed a torn ACL, and Gallardo was headed for his second surgery of the season.
Considering all he's already been through, all the Brewers are asking out of him on Wednesday is -- a lot.
How many innings do the Brewers realistically expect?
"He can go nine innings," Sveum said flatly. "If he throws 10, 11 pitches an inning. So my expectation is he'll throw a complete game, and then we'll worry about the rest of it when it happens."
Gallardo's longest two starts this season were seven innings, with the last coming on April 25 in a no-decision against the Marlins.
The right-hander made his MLB debut in 2007, and as a rookie a year ago, his longest outing was eight innings on Sept. 17 at Houston.
"I hope I can go nine," Gallardo said. "That's what I'm going to try for. It's been tough for me. Showing up in Spring Training, having my left knee surgery and missing the first couple of weeks of the season. Having three starts and getting re-injured on my right knee."
What helped pull him through was the support of his teammates, who noted that he could still be a factor despite missing so much time.
"They were pushing me every day just to rehab hard and give me an opportunity to come back," he said. "I'm just very excited. It's one of those things, to have the opportunity to go out there and start Game 1. It's an honor."
Joe Frisaro is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.