Former Trinity High School quarterback sat in the stands on Friday night at Papa John's Cardinal Stadium for the Spring Game.
And the future University of Louisville player said he got a little anxious.
"It was impressive," Bonnafon said. "I was excited to see the offense and what they can do. It's a lot different offense than what coach (Shawn) Watson had. I'm excited for it.
"It's going to be a lot of fun."
The 6-foot-1, 175-pound Bonnafon said he would enroll at U of L on June 1 and will begin classes at school on June 3.
Ranked as the No. 22 quarterback in the country by Scout.com, Bonnafon played in a system at Trinity that is "very similar" to what Petrino will run at U of L. Trinity coach Bob Beatty and Petrino are close friends, while Petrino's son – Nick – is a former quarterback who won two state titles at Trinity.
"I wouldn't say it's going to make it easy, but it will help me out," Bonnafon said. "Being familiar with the offense is a good thing for me.
"I remember being at one practice and they were doing an alley screen drill and I asked James (Quick), he said it was the same drill we did at Trinity. A lot of the concepts are the same, but the terminology is different."
Bonnafon was the first commitment of the Class of 2014 for the Cardinals and stuck through the coaching change, despite some serious interest.
Now, he's "so ready" to play for U of L.
"I can't even put it into words, it's a lifetime dream for me," he said. "I'm going to be playing for the hometown team, it's going to be so much fun. I can't wait to get going."
In his first varsity season at quarterback, Bonnafon completed 190 of 306 passes for 2,606 yards and 16 touchdowns with eight interceptions for the Shamrocks. He also rushed 165 times for 895 yards and 18 touchdowns.