NORMAN (AP) — After the shocker that turned college football on its head at the start of last season, No. 4 Oklahoma has an extra reason to be wary when a Championship Subdivision opponent rolls into town to open the season.

While Chattanooga isn’t quite Appalachian State, which was coming off its second straight national title when it upset fifth-ranked Michigan last season, that hasn’t stopped the talk around the Barry Switzer Center this week.

“The coaches have said it but they didn’t even need to say it. That’s the first thing we thought about as soon as we knew who we were playing and knew about how drastic if we lost, how that could affect our season,” defensive tackle Cory Bennett said.

There are a few similarities between Chattanooga and Appalachian State — mainly that both play in the Southern Conference — but not enough to get the Sooners too scared.

Appalachian State has won three straight national titles at college football’s second-highest level, while the Mocs are coming off a 2-9 season, which included a 37-17 loss to Appalachian State, and have had only one winning season in the past decade.

Their top running back, Bryan Fitzgerald, and starting center Brian Heflin were injured in the preseason, leaving short-handed a squad that already figured to be outmanned.

The Sooners aren’t chalking up their first win just yet, though.

“It’s a game. You’ve got to be pumped up for every game or just like last year, it’ll be one of the biggest upsets like in the Michigan-Appalachian State game. You can’t overlook anybody,” said Keenan Clayton, who’s shifting from the secondary to outside linebacker this season.