STILLWATER, Okla. -- TCU entered Saturday's game at Oklahoma State with a reputation for being a second-half team.
And with the Horned Frogs doing their best to further that tag, Cowboys running back Rennie Childs halted the storyline with a second-half breakout.
Childs, a true freshman from Houston, gave Oklahoma State's dormant running game a boost, including a 7-yard touchdown run in the fourth quarter that provided the final points in a 24-10 victory at Boone Pickens Stadium.
TCU, which trailed 17-0 at halftime, had just trimmed the lead to 17-10 with a 77-yard touchdown drive, capped by Waymon James' 13-yard scoring run.
The Horned Frogs had been all but inept in the first half, managing only three first downs and 62 yards of total offense, yet were again threatening to make a late push on Jaden Oberkom's 35-yard field goal and James' scoring run.
The Cowboys (5-1, 2-1 Big 12) and Childs answered, however.
The response started with Brandon Sheperd's 50-yard kickoff return to the TCU 47. Three plays moved Oklahoma State to the TCU 7-yard-line and Childs took it in from there, charging off the right side to score standing up with 6:04 remaining.
For Childs, who had only six carries for 15 yards entering the game, it was his first career touchdown. He finished with nine carries for 45 yards, all coming in the second half, after Oklahoma State's running game continued to sputter with Jeremy Smith and Desmond Roland at running back.
"Rennie has been close to playing the last few weeks," Oklahoma State coach Mike Gundy said. "We felt like he was mature enough in the last game, but it just never worked out that we got him in. He's been productive in practice and showing some maturity.
"It's not just running the ball. He also has to understand the offense and be successful in those other areas. We felt like it was time today."
TCU's time had been the second half. Averaging 20 points over the final two quarters, the Horned Frogs showed renewed life out of halftime again Saturday.
"We came out in the second half with our backs against the wall, and that's when we play our best football," TCU guard Eric Tausch said. "If we could only play like that in the first half, then the sky's the limit for our offense."
While the Horned Frogs were much better on offense in the second half, they weren't good enough. Quarterback Trevone Boykin threw his third interception in the third quarter, ending one possession, and TCU was twice stopped on fourth-down tries.
"When you play at somebody else's place, you have to play to win" TCU coach Gary Patterson said of the fourth-down gambles. "We hadn't been down there (in the red zone) very often, but when you get down there, you have to get more than three points."
Along with Childs, the Cowboys got a lift from backup quarterback Clint Chelf, who came on to throw for 178 yards and a touchdown in relief of starter J.W. Walsh, who tossed two early interceptions.
"I think it comes to a certain point where you have to make a decision," OSU offensive coordinator Mike Yurcich said. "I don't know if it was exactly this or that, it was just time, I guess."
The first half featured six turnovers, three by each team, two missed field goals by the Cowboys and a punt return for a touchdown by Oklahoma State, Josh Stewart going 95 yards for the game's first score.
While the Cowboys led only 17-0, it felt like much more, with TCU managing but three first downs and 62 total yards.
Stewart was the star of the half, with his first-quarter return sending his team in front, along with eight catches for 106 yards. He finished with 10 receptions for 141 yards, going against a secondary considered one of the Big 12's best.
"When you hear stuff all week about the level of secondary you will be playing against, it makes me want to make plays for my team," Stewart said. "I had opportunities and I just made the best of them."
The Cowboys padded their lead on a 28-yard field goal by Ben Grogan and Desmond Roland's 3-yard scoring run.
Still, Oklahoma State wasted more opportunities.
The Cowboys punted only once in the first half, threw three interceptions in TCU territory, including one in the end zone, were stopped on downs at the TCU 17 and missed field goal attempts of 31 and 32 yards.
The Horned Frogs (3-4, 1-3) mostly sputtered, when they weren't turning it over. Boykin threw two interceptions, while completing 5-of-13 passes for 27 yards.
Backup Tyler Matthews appeared briefly, missing his only passing attempt. TCU ran 14 times for 35 yards.
NOTES: Stewart's 95-yard punt return for a touchdown was the longest in school history. It also was the longest return in FBS this season, bettering the 88-yard runback by Louisiana-Monroe's Rashon Ceaser against Tulane on Sept. 28. ... TCU entered the game tied for the Big 12 lead with 15 takeaways, while Oklahoma State led the league in turnover margin. The teams combined for eight turnovers Saturday. ... The crowd of 59,638 set a Boone Pickens Stadium record.