The 28-year-old right-hander suited up for the Missions for the first time since Aug. 29, 2007 and took a no-hitter into the eighth inning Friday as the Missions beat the Frisco RoughRiders, 5-2.
The outing capped a roughly 4 1/2-year journey during which Geer was named 2007 Texas League Pitcher of the Year, made his Major League debut with San Diego in 2008 and returned to the Minor Leagues in 2009-10.
All of that came before he missed nearly all of last season after undergoing surgery for melanoma in his lymph nodes.
"I had to go to chemotherapy all of last year, miss the season. That stopped in December and I was able to come back for Spring Training," Geer said. "It's my first year back, so it was mostly about getting my body weight back, getting my energy back.
"I feel good, feel pretty much back to normal. The energy level is pretty much there, now it's just about finding that release point and staying consistent."
Geer started the year with Triple-A Tucson, where he compiled a 7.81 ERA over 40 1/3 innings. He returned to San Antonio to work on building his energy level and returning to the form he showed in his last go-round in the Texas League. In 2007, he was 16-6 with a 3.20 ERA for the Missions.
A year and a day following his final start of 2007, he earned the win in his first big league start at Petco Park.
On Friday, he was back with Missions, discovering that surprisingly little had changed, both with the team and the ease with which he dispatched Texas League opponents.
"That's the longest I've ever gone with a no-hitter. It was definitely cool," said Geer, the Padres' 2005 third-round Draft pick. "It was just a crazy thing. I was talking with our hitting coach, Tom Tornincasa, who was here [in 2007]. I even had the same number as in 2007, too."
Geer said he wants to continue gaining strength and getting back his feel for pitching while trying to advance back up the San Diego system. At the very least, he can feel safe knowing it's not the toughest battle he's fought.
"It was just a crazy ordeal, the whole thing. But it feels good to be back here," he said. "Obviously, I'd rather be in Triple-A or the big leagues, but it feels good in a way."
Geer allowed only three baserunners through seven innings -- Jurickson Profar and Engel Beltre walked and Chris McGuiness reached on an error. But Jared Prince ripped a double on the Texas native's first pitch in the eighth.
Padres' No. 15 prospect Edinson Rincon doubled and drove in three runs, while Jonathan Galvez chipped in a pair of RBIs in support of Geer.
Profar, the Rangers' top prospect, led off the ninth with a triple off reliever Matt Lollis to extend his hitting streak to 28 games.