Petrino said he was hesitant to start him on such a big stage against Auburn.
But eventually the Cardinals' threw Jackson into the mix and now Petrino has named him as the starting quarterback moving forward. Jackson is expected to start for the Cardinals on Saturday against Houston in Papa John's Cardinal Stadium.
"Based on what I saw from him, yeah," Petrino said when asked if Jackson was the starter.
The 6-foot-3, 195-pound Jackson came in against Auburn in the second quarter and completed 9 of 20 passes for 106 yards and ran 16 times for 106 yards and one touchdown.
Jackson helped rally the Cardinals' from a 24-0 deficit in the 31-24 loss to the Tigers.
"Lamar is the most exciting quarterback in college football right now," freshman wide receiver Jaylen Smith, who is Jackson's roommate, said. "Lamar has a great arm. He can probably throw a ball 85 yards.
"His throws are very accurate and they have high velocity. It gets there very fast."