The Sooners just went out and proved how deserving they are of that playoff berth coming their way by dominating TCU again, 41-17 on Saturday in the second top-10 matchup in four weeks between the Big 12's top two teams.
"I'm really proud of our group for not listening to the entire narrative across the country that we shouldn't be playing this championship game and all that mess," coach Lincoln Riley said. "We knew there was going to be a championship game and that was just going to be part of our journey if we wanted to get to this place."
Mayfield, the Heisman Trophy front-runner, threw four touchdown passes as Oklahoma (12-1, CFP No. 3) won its record 11th Big 12 title.
"The reason I came back was to play for a national title," Mayfield said. "The most exciting thing about today is we control our destiny. ... That's all out in front of us."
The Sooners are a lock Sunday to be in the College Football Playoff for the second time in three seasons. They are the only Big 12 team to make the four-team playoff format that started in 2014.
Mayfield was so confident in the Sooners winning their third straight Big 12 title that in postgame he wore a shirt he had from back-to-back championships that already been updated, showing the three in a row he has won since transferring from Texas Tech.
"I had it updated before Bedlam," Mayfield said, referring to game against rival Oklahoma State a month ago.
The Sooners probably would have made the playoff even if the Big 12 hadn't played its first championship game since 2010. But a loss would have likely knocked OU out of contention.
Oklahoma jumped out to a quick 17-0 lead, including Caleb Kelly's 18-yard fumble return for a touchdown after running back Kyle Hicks' turnover on the first offensive play by TCU (10-3, No. 11).
Kenny Hill threw two TD passes to get the Horned Frogs within 24-17 at halftime, but Oklahoma was in total control after scoring twice on its first three offensive plays after the break.
"Big plays, we gave up a couple. ... Two plays basically in the second half," TCU coach Gary Patterson said. "The worst thing that could happen in the third quarter happened."
A week before the Heisman winner will be named, Mayfield finished 15-of-23 passing for 243 yards and took game MVP honors. His first two touchdowns were to tight end Mark Andrews .
Hill opened the second half with three consecutive incompletions. On the first play after the punt, Mayfield hit Mykel Jones for a 55-yard catch-and-run score.
A fourth-and-1 stop by Oklahoma's defense, led another Sooners touchdown. Marquise Brown made an impressive over-the-shoulder grab for a 52-yard TD and a 38-17 lead.
Hill, who started his college career at Texas A&M behind Heisman Trophy winner Johnny Manziel, was 27-of-37 for 234 yards passing, and led TCU with 51 yards rushing.
"It's been a fun ride and a wild ride, and I think this guy (Patterson) here for giving me the opportunity to come here and play," Hill said. "As far as Baker goes, man, he looks like the Heisman."
TCU: The Horned Frogs had allowed only six points (two field goals) combined after halftime in their last seven games. Even Oklahoma was scoreless in the second half of its 38-20 home win on Nov. 11. The 41 points are the most TCU has allowed this season.
Oklahoma: The Sooners' 11th Big 12 title overall was the first without Bob Stoops, the coach for their last national title in 2000 who resigned unexpectedly last summer. Riley, at 34 the youngest FBS head coach, is only the fifth coach in FBS history with no previous head coaching experience at a four-year college to win at least 12 games in his debut season.
Oklahoma is 8-1 in Big 12 championship games, winning seven of them between 2000 and 2010, when the Sooners beat Nebraska in the league's last championship game until Saturday.
TCU was within 17-14 when John Diarse made a one-handed TD grab before falling out of bounds. Initially ruled an incompletion, TCU had a touchdown after the replay review. Diarse had immediately run to the sideline and told Patterson it was a catch. "I told him I would take it as a catch as soon as they put their hands up," the coach said.
TCU: The Horned Frogs could still possibly make it into one of the New Year's Six bowl games, and if not likely will be the Big 12 representative in the Alamo Bowl.
Oklahoma: The Sooners wait to find out who they will play and in which national semifinal game, the Rose Bowl or Sugar Bowl.
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