AMES, Iowa (AP) Third-ranked TCU has made it through the toughest stretch of the season with its playoff hopes intact.
Now the Horned Frogs have a week to rest up before their final push for the Big 12 title and beyond.
Trevone Boykin threw for 436 yards and four touchdowns and TCU rolled past Iowa State 45-21 on Saturday night for its third road win in four weeks.
Josh Doctson had 190 yards receiving and two TDs for the Horned Frogs (7-0, 4-0 Big 12), who went on a 31-0 run after another sluggish start.
''We have to quit playing tentative when we go on the road...once we get them settled down and get into rhythm, then it's been ok,'' TCU coach Gary Patterson said.
Once again, Boykin led the way.
His 3-yard touchdown run with 14:36 left put TCU ahead 38-21, and he and Doctson made it a rout by hooking up for a 42-yard scoring strike 6 six minutes later.
Boykin finished with 510 yards of offense and five total touchdowns in leading TCU to a school-record 15th straight win dating to 2014.
''He's a special athlete, so you've got to defend him all the time - run, pass, whatever he does,'' said Iowa State coach Paul Rhoads. ''If your kids aren't in position and there to finish, they're going to complete those.''
Sam Richardson had 251 yards passing for Iowa State (2-4, 1-2), which stoked its hopes for an upset by taking a 21-14 lead in the first.
TCU dashed their dreams with a pair of long drives and a suddenly stout defense.
The Horned Frogs went 86 yards to open the second half, and a 13-yard touchdown run by Kyle Hicks made it 31-21. Nick Orr forced a fumble on a blind side blitz to kill an Iowa State drive, and Boykin's touchdown run capped an 85-yard drive that put Iowa State behind by 17.
Freshman Mike Warren had just 78 yards rushing for Iowa State. Warren had averaged 182 yards over his three previous starts.
''It's a huge confidence (boost) for those guys,'' Boykin said of the defense's second-half shutout.
Rhoads had preached to his team all week about the importance of a fast start.
The Cyclones got one, with a 74-yard touchdown reception by Allen Lazard - who finished with 147 yards on five catches - bookended by short scoring runs by Thomas and Warren in the first quarter.
''We might the worst first quarter defense in college football right now. Holy smokes,'' Patterson said.
TCU started just as quickly though, scoring on TD throws from Boykin to Doctson (20 yards), Kolby Listenbee (21 yards) and Charlie Reid (14 yards).
It wasn't surprising to see the Horned Frogs let the Cyclones hang around after close road wins over Minnesota, Texas Tech and K-State.
But after allowing 262 yards in the first quarter, TCU allowed just 199 the rest of the way.
The Horned Frogs, who've battled injuries all year, lost wide receiver KaVontae Turpin with an apparent upper-body injury. Patterson didn't elaborate on Turpin's injury other than to say it wasn't season ending.
They'll be able to sit Turpin and everyone else for at least a few days before returning to host reeling West Virginia on Oct. 29.
''We're beat up pretty good,'' Patterson said. ''We're going to need the 12 days to get ourselves back and ready to go. It's good to go into a break undefeated.''
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