Garoppolo replaced Lynch after his better known counterpart from Northern Illinois threw a couple of early interceptions and wound up stealing the show.
Coastal Carolina's Matt Hazel scored on a 1-yard reception to Garoppolo, who completed nine of 14 passes for 100 yards and no interceptions to earn offensive MVP honors for the East in a 23-13 victory.
Nevin Lawson returned a fourth-quarter fumble 5 yards for another TD to help seal the win before an announced crowd of 19,500 at Tropicana Field.
"I wasn't used to coming off the bench, so I had to get warmed up. But the coaches called some good plays to get me in a rhythm, and the offensive line did a great job as well," Garoppolo said.
"Out here it's just about the competition, whether you're at a small school or a big school you still have to show you can get the job done," the Eastern Illinois quarterback added. "I believe I'm one of the best players in the nation, and that's the mindset I play with."Arkansas' Zach Hocker kicked three field goals for the East, including a 56-yarder that snapped a 13-13 tie early in the fourth quarter.
Lawson, a cornerback from Utah State, scooped up a fumble forced by Western Kentucky's Andrew Jackson to put the East up 23-13 with 9:38 to go.
Lynch, who was not available for postgame interviews, started for the East and threw a pair of first-quarter interceptions while also failing to get his team into the end zone after West starter Keith Wenning of Ball State lost a fumble at his own 22 on the second play of the game.
Hoping to capitalize on the quick turnover, Lynch overthrew potential scoring passes to Michigan's Jeremy Gallon and Miami's Allen Hurns before the East settled for a 31-yard field goal. Two of his next three passes were intercepted by Arizona State's Alden Darby and Arizona's Shaquille Richardson.
The East defense, led by West Virginia lineman Will Clarke and team defensive MVP Ethan Westbrooks of West Texas A&M, forced four turnovers.
"This was a great way to end my college career. It was a great week on and off the field," Westbrooks said. "I always thought I could play at this level, and playing against guys on the same level or better than you always brings out the best."