ARLINGTON, Texas (AP) — Spencer Rattler threw a 45-yard touchdown to Marvin Mims and also ran for a score as No. 12 Oklahoma won its sixth consecutive Big 12 title, holding on to beat No. 8 Iowa State 27-21 in the conference championship game Saturday.

That impressive title streak probably won’t be enough to get the Sooners (8-2, No. 10 CFP) back in the College Football Playoff for the fourth year in a row, even when paired with their seven-game winning streak. Oklahoma lost at Iowa State on Oct. 3 and was 0-2 in Big 12 play for the first time since 1998.

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Big 12 rushing leader Breece Hall ran for two touchdowns for the Cyclones (8-3, No. 6 CFP) in the second half, when Oklahoma punted on its first five drives before Gabe Brkic’s 32-yard field goal with 2:01 left. The Sooners finally clinched the game when Iowa State quarterback Brock Purdy was under pressure and threw his third interception, a fluttering pass picked off by Tre Brown inside the 10.

The Sooners will play in a New Year’s Six game, probably back at AT&T Stadium, after winning their fourth Big 12 championship in a row since the title game was reinstated — with four different starting quarterbacks. Rattler, who finished 22-of-34 passing for 272 yards and his 25th TD, is the first of those QBs who went to Oklahoma as a freshman instead of transferring into the program.

Iowa State played in a conference championship game for the first time in school history, though fifth-year coach Matt Campbell was incensed at times. Standout defensive back Isheem Young was ejected after a questionable targeting call in the opening minute, and the Cyclones later didn’t get a fourth-down call when trying to draw Oklahoma offside even when two Sooners appeared to jump over the line.

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Rattler hit Mims in stride behind two defenders on the opening play of the second quarter to put Oklahoma up 14-0. That came after a 16-yard catch by Mims to end the first quarter on a pass that first deflected off two defenders. Campbell lost it on the sideline, pointing and screaming, but like his team calmed down and got back in the game.

After Iowa State finally scored with 1:34 left in the first half on Purdy’s 10-yard touchdown pass to tight end Charlie Kolar, the Sooners got a 43-yard kickoff return from Brown. That set up a quick four-play drive capped by Rattler’s 9-yard keeper for a 24-7 halftime lead.

Oklahoma led throughout, scoring on the game’s opening drive when third-string freshman quarterback Chandler Morris came in for a 2-yard TD keeper. Brkic, who was just wide right on a 43-yard field goal attempt, was later good on a 54-yarder that was the longest for the Sooners since 1990.

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