"You know their eyes are just wide open," Larsen said. "After two plays, it's not quite as fast. Darell came out with that same confidence that Chuckie did as a freshman."
Yet, Garretson's situation will be wildly different from the one Keeton walked into when Utah State meets New Mexico Saturday night at University Stadium in Albuquerque.
While Keeton spent that first summer preparing to compete for the starting job, Garretson was supposed to have a season or two before battling to take over. He competed with Craig Harrison and Jeff Manning just for backup reps, and he didn't see many once the season started. USU would have likely redshirted him this season if things had gone as planned.
The Aggies have struggled to put points on the board since Keeton's season-ending knee injury, but the Aggies still believe Garretson has the talent to fill in under center and revitalize a stalled offense over the final five games of the season.
"He was kind of groomed for this," offensive coordinator Kevin McGiven said. "His dad was a coach, and for these pressing moments, I think he's been kind of primed for it. He understands the game, what kind of demeanor it takes, and he's handled it with the team really well."
If Garretson seems more prepared to take over as starting quarterback, it may be because he's done it before.
When he was a sophomore at Chandler High (Ariz.) in 2010, Garretson took over at quarterback for an injured starter for the then-No.2 ranked Wolves. He wasn't spectacular, but played solidly against returning state finalist Desert Vista, throwing two touchdowns in a 28-21 loss.
That starter he replaced was Brett Hundley, the future UCLA star whose numbers he would eventually eclipse in the Chandler record books. Garretson ended up throwing for 3,065 yards and 27 touchdowns as a senior, earning multiple awards as the top quarterback in Arizona last fall.
"I think fighting through that adversity as a sophomore helped shape him," Chandler coach Shaun Aguano said. "From a mental standpoint, he's very mature for his age. It was tough for him to come in against Boise State, but he's been used to getting thrown in the fire."
Of course, there are other factors that have helped Garettson develop. His father, Rick Garretson, is a longtime high school coach who has drilled playbooks into his son over the years. He's related to two NBA referees grandfather Darrell was the longtime director of officials for the league so he respects what it means to have deep understanding of the game.
The system Garretson ran in high school has a lot of similar elements to the one he runs with the Aggies, McGiven said. He also has three Chandler teammates on the team Devin Centers, Jeremy Morris and Michael Okonkwo who have helped him feel a little more at home.
Utah State at New Mexico
O At University Stadium, Albuquerque, N.M.
Kickoff • Saturday, 7 p.m.
TV • ROOT
Radio • 1280 AM
Records • Utah State (3-4, 2-1); New Mexico (2-4, 0-2)
Series history • New Mexico leads 11-8
Last meeting • Oct. 4, 2003, at UNM; UNM 34, USU 7
About the Aggies • Utah State has the top-ranked defense in the Mountain West and the No. 29-ranked rushing defense (129.1 ypg) in the nation.
About the Lobos • New Mexico averages 349.3 rushing yards per game, No. 2 in the nation. … Running back Kasey Carrier is eighth nationally with 131.5 ypg and has eight rushing touchdowns this year.