Watch Now: No. 4 Ohio State defeats No. 15 TCU 40-28 (1:30)

Ryan Day's final game as the acting head coach of No. 4 Ohio State was the signature win of his very brief stint. The Buckeyes outlasted No. 15 TCU 40-28 at AT&T Stadium in Arlington, Texas, Saturday night in an old-fashioned, Texas-style showdown that will likely carry enormous College Football Playoff ramifications when the committee begins to release rankings.

It was a huge win over a ranked opponent only 20 minutes away from their turf, in the final game of permanent head coach Urban Meyer's three-game suspension. 

The Horned Frogs aren't dead yet, though. They ran out of gas late, but Shawn Robinson's work under center and Darius Anderson erupting as a big-play threat makes them a big factor in the Big 12.

What did we learn about the Buckeyes and Horned Frogs Saturday night deep in the heart of Texas?

1. The Buckeyes are relentless: If wins over lowly Rutgers and Oregon State weren't enough to solidify Ohio State as a 900-pound gorilla ready to take on any and all comers in 2018, Saturday's win seals it. Quarterback Dwayne Haskins was tremendous, completing 24-of-38 passes for 344 yards, two touchdowns, zero interceptions and one rushing touchdown. He operated the offense like a seasoned veteran, didn't panic when massive momentum swings favored TCU and ultimately iced the game with a 24-yard touchdown pass to K.J. Hill in the third quarter, and a five-yard touchdown run in the fourth quarter.

Whether it was Haskins on his own, Hill on his birthday, Parris Campbell or J.K. Dobbins (who had 121 yards on the ground) the Buckeyes just kept coming all night long.

It wasn't just offensively, though.

The defense -- without star defensive lineman Nick Bosa for the majority of the second half -- came after Robinson early and often. Robinson stood tall for a while, but Dre'Mont Jones' 28-yard pick six in the third quarter contributed to the relentless nature of the Buckeyes. 

Ohio State not only proved that it was legit, but proved that the off-field drama leading up to the season didn't affect the on-field product, and the Buckeyes are the Big Ten's version of Alabama and Clemson. Terrifying.

2. Don't count TCU out: The Horned Frogs ran out of gas in the second half, but don't let that distract you from what they proved against the Buckeyes. This team is legit, complete and a factor in the Big 12 and College Football Playoff races.

This was the first big stage for Robinson, and he responded with 308 passing yards in the face of one of the toughest defenses in the country. Anderson popped off two touchdown runs including a 93-yarder, and the Jalen Reagor hauled in seven passes for 98 yards. 

The stat sheet doesn't look great on the defensive side. After all, 526 yards and 6.6 yards per play won't vault the Horned Frogs up the national rankings. But they didn't break in the first half and did all they could in the second half before Ohio State's depth wore them down.

But in the Big 12, how much will that matter. TCU's offense proved to be solid against Ohio State, it's defense had more than a few moments of brilliance and outside of Oklahoma, is there another complete team in the conference? Probably not. So for TCU, the goal is simple. Take care of business in the Big 12, earn a bid in the conference championship game and hope for a little chaos around the country. 

Considering the way the Horned Frogs looked against Ohio State, a little chaos could go a long way for a team that has a ton of potential in 2018.

3. Ohio State needs Nick Bosa: The star defensive end and likely first-round draft pick left the game in the third quarter with a groin injury, and returned in street clothes to cheer on his teammates late in the game.

He had five tackles and a sack prior to heading to the locker room, but the Buckeyes found away to make up for his absence. 

But what if the injury lingers?

He was pulled from action rather quickly, and there's no doubt that the Buckeyes defense needs its star for the long run. With Penn State lurking in two weeks, the Big Ten East could be won or lost based on the result of that game. Meyer likely won't need Bosa against Tulane next week, but will against Trace McSorley and the Nittany Lions. 

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