FORT WORTH, Texas -- Trevone Boykin passed for a career-high 460 yards and caught a touchdown pass as No. 3 TCU earned at least a share of the Big 12 championship and kept its playoff bid alive with a 55-3 victory against lowly Iowa State on Saturday. The Horned Frogs (11-1, 8-1 Big 12) came into championship weekend ranked third in the College Football Playoff selection committee's rankings. TCU was the only playoff contender not playing a ranked team this weekend.

There wasn't much the Frogs could do help themselves against the Cyclones (2-10, 0-9), but they avoided the type of clunker that could have caused the committee to downgrade them.

Aaron Green scored two touchdowns for TCU and Derrick Kindred returned an interception 44 yards for a score in the third quarter to put the Frogs up 34-3.

Iowa State finished winless in the Big 12 for the first time since 2008, and the first time under sixth-year coach Paul Rhoads.

For TCU the question was not if the team would win, but by how much? The Horned Frogs were 34-point favourites against the worst team in the Big 12. The Cyclones have been crushed by injuries and no team in the league has allowed more yards per play.

To complete their resume and make sure they stay ahead of Ohio State and Baylor when the final playoff rankings are revealed Sunday, the Frogs needed to exert some serious game control.

Despite losing 61-58 at Baylor in October, the Horned Frogs will be able to put conference champion on their resume no matter what the Bears do tonight, 85 miles south of Fort Worth in Waco, against Kansas State.

The Big 12 won't designate a champion through a tiebreaker. Instead, the conference will let the committee sort it out. The selection protocol states that championships won and head-to-head are supposed to be used as determining factors when choosing between similar teams.

Committee chairman Jeff Long said again on ESPN on Saturday morning that the head-to-head between TCU and Baylor hasn't "come into play yet."

The Frogs and Bears play 10 common opponents. The biggest difference is Baylor played at Buffalo, a mediocre Mid-American Conference team, and TCU played Minnesota, a good Big Ten team.

If this is the weekend the head-to-come comes into play, it had nothing to do with what TCU did Saturday.

The 11 a.m. local time kickoff, combined with an opponent the Frogs were expected to dominate, created an odd big-game atmosphere at Amon G. Carter Stadium. The stands were packed with purple, except for an Iowa State section that had plenty of room to stretch out, but it was a relatively low energy crowd for senior day.

Boykin's first career touchdown reception got TCU off to a good start. The junior threw a backward pass to David Porter, who threw back to Boykin, behind a wall of blockers. The quarterback, who had 26 catches last season playing receiver, went untouched into the end zone from 55 yards out.

Green's 3-yard touchdown run made it 14-0 in the first quarter.

Then a penalty here, a negative red-zone play there and a couple of turnovers kept TCU from pulling away in the first half. The teams traded field goals in the second quarter and it was 17-3 at the break. The Frogs outgained Iowa State 343-138 in the half.

If there was any anxiety in Carter Stadium, it went away soon after the second half kickoff. Green took a swing pass and raced 54 yards for a touchdown to make it 24-3 just 66 second into the second half. The expected rout was on.