After circling the Horseshoe with the Oklahoma flag, quarterback Baker Mayfield runs to midfield and stabs the Ohio State logo surrounded by teammates. (1:10)

COLUMBUS, Ohio -- Quarterback Baker Mayfield said planting the Oklahoma flag on Ohio State's logo at midfield of "the Shoe" was a "last-minute" decision, but that he was planning on putting some sort of exclamation point on the fifth-ranked Sooners' 31-16 victory over the No. 2 Buckeyes.

"Part of it was [what happened] last year," said Mayfield, referring to Ohio State's 45-24 rout of Oklahoma in Norman. "It was embarrassing for them to sing their fight song on our field. They're probably feeling the same way right now."

Mayfield took the flag near from where the Oklahoma band was in one corner of Ohio Stadium, ran with it down the opposite sideline, then dashed to midfield, where many of his teammates were waiting. He jabbed the turf with the flag as his teammates cheered.

Mayfield, who completed 27 of 35 passes for 386 yards and three touchdowns on Saturday, said the celebration also stemmed from few picking his Sooners to win.

Oklahoma was better than a touchdown underdog against Ohio State.

"It was embarrassing for them to sing their fight song on our field. They're probably feeling the same way right now," Sooners QB Baker Mayfield said of Ohio State. Gregory Shamus/Getty Images

"We've had this mood in the locker room that no one believes in us," Mayfield said. "The guys were able to catch the fact that no one picked us from College GameDay. You see it on social media throughout the week that 80 percent of the country voted for Ohio State to win.

"We believe in ourselves, and quite frankly, that's all that matters."