Garretson, who finished his rookie season 126 of 209 for a freshman record 1,446 yards and 10 touchdowns, is fine with the role, not that he'd have much choice in the matter.
As good as he was last year, Garretson said he knows Keeton is a special player who the Aggies are lucky to have.
"I'm being bumped by a great player," he said. "He takes things to a new level for us and it's his team. He earned that right. He is a Heisman candidate."
As agreeable as Garretson is to being a backup once again, don't think for a second the sophomore is looking at the 2014 season as some sort of throwaway year before he can walk into the starter's role.
The youngster is savvy enough to know unpredictable things can happen and he could be thrown right back into the fire just like he was last year a wild ride of a time that he needed to put into context when it was all over.
"When the season was over, my dad and I talked a long time about what happened," he said of his transformation from a bench warmer to starter. "I just had to laugh at it all. It was fun and looking back on it all, I'll always cherish what happened last year for me."
Garretson might not be in the starting lineup, but he isn't being cast aside either. He'll continue to get some time with the starters in camp, coach Matt Wells said.
"Just watching him he doesn't look like the young 18-year-old that we were trying to redshirt last year," Wells said. "He's got some confidence, which he should, and he came in and did a good job last year."
Wells hasn't discounted the possibility of redshirting Garretson, especially with senior Craig Harrison available. Harrison has played in 16 games, completing 43-of-83 passes for 497 yards and two touchdowns.
Regardless of whether Garretson redshirts, the Aggies' stable of quarterbacks looks healthy for the future.
The Aggies will have Damion Hobbs, the transfer from Oregon, available to play next season and Kent Myers, a freshman out of Texas. The Aggies also have a commitment from Kareem Coles, a quarterback out of California, who plans to sign in February.
Knowing all that talent is around him will keep Garretson motivated.
"My confidence is up," he said. "I've been through the fire, but I still have to keep improving and getting better. You never know when you could get thrown in."
Darell Garretson file
Vitals • 6-foot, 200 pounds, sophomore.
From • Chandler, Ariz.
Of note • He set a school record by winning his first five starts…Completed 60.3 percent of his passes (126 of 209) as a freshman to rank fifth all-time in school history for a single season…Set the freshman passing record by throwing for 1,446 yards…Earned academic All-Mountain West honors in 2013.