"It has their attention," Petrino said.
And in the future, Petrino is hoping to get an opener as tough as Auburn for every season. The second-year coach at U of L said the competitive opener keeps the players focused the entire offseason.
"Our goal is to win a national championship and get to the playoffs," Petrino said. "So, that's what we're going to continue to do. Our philosophy will be to open with a big game almost every year."
The Cardinals open with Auburn on Sept. 5 in the Chick-Fil-A Classic this season in Atlanta, while the Cardinals will host Charlotte on Sept. 3 in the 2016 opener.
In 2017, the Cardinals will play Purdue in Lucas Oil Stadium and there's no planned game at this point for '18. The Cardinals host Notre Dame on Sept. 2 to open the 2019 season on Labor Day night.
"We're going to continue to try and play a tough game in the opener," Petrino said, noting his program was close to announcing a future opener in Orlando, Fla.