Jesse Scroggins was in high school when he saw it happen to USC two years ago against Washington.
He was redshirting last season when it happened again against Notre Dame.
In both instances, Trojans quarterback Matt Barkley was unable to play because of injuries, thrusting his backup into the starting lineup.
"It's always just one play away," Scroggins said Thursday.
As the Trojans prepare for another Saturday scrimmage at the Coliseum, Scroggins appears on track to become the Trojans' No. 2 quarterback.
Coach Lane Kiffin said this week that the redshirt freshman from Lakewood had moved ahead of freshmen Cody Kessler and Max Wittek, though a decision on Barkley's backup might not come until the fall.
Regardless, the 6-foot-3, 205-pound Scroggins continues to develop in and out of the huddle.
"Being a USC quarterback is different from any other college," he said. "I feel I'm starting to get that."
Scroggins said he is working to overcome his "shy side" and to become "that guy."
"You've got to be the leader," he said. "You've got to be the guy that everybody likes."
With center Khaled Holmes sidelined because of a neck condition, left tackle Matt Kalil is the only offensive lineman who has established himself as a starter.
"That will be the No. 1 question, by far, on our team [in the fall]," Kiffin said of the offensive line.
Sophomore John Martinez, senior Martin Coleman, freshman Giovanni Di Poalo and junior college transfers Jeremy Galten and David Garness have gotten extensive work. Kiffin has been impressed with Galten's toughness in playing with a knee sprain but said "none of those guys have performed like starters would need to for us."
Kiffin added that "Some guys aren't developed enough. Some guys aren't playing fast enough because they're new to it and so they haven't caught on to the system. So this off-season will be big for them and obviously this fall."
In the swing
Barkley, safety T.J. McDonald and other players took batting practice at Dedeaux Field after Thursday's workout.
McDonald, a junior, said he enjoyed watching former major leaguers Ken Griffey Jr. and Sammy Sosa when he was younger and contemplated playing baseball at USC in 2010. (Safety Jawanza Starling played in nine baseball games for the Trojans last spring).
McDonald put off baseball plans after the football coaching staff changed following Pete Carroll's departure. McDonald, after off-season ankle surgery, wanted to make an impression on the newcomers.
"It was the coaches' first spring," he said. "They didn't know what I could do."
Linebacker Hayes Pullard, a redshirt freshman from Crenshaw High, continues to impress, Kiffin said…. Tight end Rhett Ellison worked at fullback and could line up there more if a trio of young tight ends —sophomore Christian Thomas and redshirt freshmen Xavier Grimble and Randall Telfer — continues to develop, Kiffin said.