If you’re an Ohio State football fan, you’ve probably already had Sept. 15 circled on your calendar for quite some time.

While the Buckeyes will open their 2018 season at Ohio Stadium on Sept. 1 against Oregon State, and will host Rutgers in their first Big Ten game of the season one week later, both of those games are expected to be decisive victories in favor of the home team. Ohio State is projected as a 32.5-point favorite over Oregon State, according to sportsbook 5Dimes, while Rutgers has lost its first four meetings with the Buckeyes by a combined score of 219 to 24.

On Sept. 15, however, Ohio State should face its first real test of the season, when the Buckeyes return to AT&T Stadium in Arlington, Texas, for the second time in nine months, to face TCU in its backyard.

While TCU doesn’t carry the same brand name gravitas as Oklahoma – the Buckeyes’ marquee non-conference opponent of the last two seasons – the Horned Frogs are projected to be among the top teams in college football this season, and perhaps the Sooners’ top competition to defending their Big 12 title. USA TODAY’s Paul Myerberg ranked TCU eighth in his post-spring preseason top 25, while Sports Illustrated’s Chris Johnson ranked the Horned Frogs ninth.

As such, Ohio State’s third game of the season – a game that will be nationally televised in primetime on ABC’s Saturday Night Football, as announced Wednesday by ESPN – could be the first true measure of the 2018 Buckeyes, with Dwayne Haskins at quarterback and new starters at several other key positions, and how they stack up against top competition this year.

The Horned Frogs, who have been among college football’s most consistent teams since Gary Patterson became their head coach in December 2000, have won at least 11 games in three of their last four seasons, including last season, when they went 11-3 and finished as Big 12 runners-up.

TCU is replacing some key players from last year’s team, including starting quarterback Kenny Hill and offensive tackles Joseph Noteboom and Matt Pryor. Key departures from TCU’s defense include four first-team All-Big 12 performers: Linebacker Travin Howard led last year’s Horned Frogs with 108 total tackles, defensive end Mat Boesen led last year’s team with 11.5 sacks, cornerback Ranthony Texada led last year’s team with 15 passes defensed and safety Nick Orr led last year’s team with three interceptions.

At the same time, the Horned Frogs are still returning some of their top players from last season, and have enough rising talent to end up emerging as a national contender once again.

"Re-evaluating TCU’s odds reveals a team loaded and ready at nearly every position, though the offensive line needs to round into form before September," wrote Myerberg, who ranked TCU as college football’s 22nd-best in his initial preseason top 25 before elevating the Horned Frogs to eighth after spring practice.

TCU’s new starting quarterback is expected to be Shawn Robinson, a four-star recruit who completed 13 of 27 passes for 184 yards and three touchdowns and ran 23 times for 159 yards last season as a true freshman. Most of that action came against Texas Tech, when he filled on an injured Hill and led the Horned Frogs to a 27-3 win.

Robinson’s passing accuracy looms as a question going into the season, but he’s a dual-threat who has demonstrated the athleticism to make big plays with his feet and the big arm to throw the deep ball.

"I’m trying my hardest to make it my offense," Robinson said last month, according to Stefan Stevenson of the Fort Worth Star-Telegram. "Being a quarterback you need to be a leader. I'm working on stepping up and being more of a vocal leader and a better passer."

Robinson should have a good group of weapons around him, including two of the Horned Frogs’ top three rushers from last season.

Darius Anderson, who led TCU with 768 rushing yards and eight touchdowns last season despite missing the Horned Frogs’ final four games of the year, is back after earning honorable mention All-Big 12 honors in 2017.

Sewo Onilula, who ran for 330 yards and seven touchdowns on just 64 carries last season, is back in the fold as well. ESPN’s Jake Trotter recently named him as TCU’s breakout player of the spring, describing the 6-foot-3, 231-pound running back as the "perfect power complement" to Anderson.

At wide receiver, the Horned Frogs have another rising star in Jalen Reagor, who led TCU with 576 receiving yards and eight receiving touchdowns on 33 catches as a true freshman last season. Reagor was named as last season’s Big 12’s Co-Offensive Freshman of the Year, and that was before his 169-yard performance in TCU’s season-ending win over Stanford in the Alamo Bowl.

Senior wide receiver KaVontae Turpin, meanwhile, is not only a playmaking threat on offense as a pass-catcher and a runner, but also one of the nation’s top return specialists. Turpin scored touchdowns as both a kickoff and punt returner in 2017 while catching 41 passes for 394 yards and another touchdown and running 11 times for 86 yards and two touchdowns.

The biggest question for the Horned Frogs entering the season, as mentioned by Myerberg, is their offensive line, where left guard Cordel Iwuagwu is the only returning full-year starter from last season. Outside of Iwuagwu and Lucas Niang, who started eight games at right tackle last season, the rest of the Horned Frogs’ starting offensive line will be brand new.

The Horned Frogs have some talented players competing for the open starting spots, including Anthony McKinney, a four-star junior college transfer, who could be an immediate starter at left tackle. Building cohesion with an inexperienced offensive line, though, could be the steepest and most crucial challenge for TCU between now and Sept. 15, when the Horned Frogs will absolutely need strong play up front against Nick Bosa, Dre’Mont Jones, Chase Young and the rest of Ohio State’s defensive line.

On the defensive side of the ball, the star among TCU’s returning players is Ben Banogu, who earned first-team All-Big 12 and Big 12 Defensive Newcomer of the Year honors last season after transferring from ULM. A defensive end who has the potential to emerge as a top prospect for the 2019 NFL draft (though the defensive line class is loaded), Banogu led the Horned Frogs with 16.5 tackles for loss in 2017.

Another top player on TCU’s defensive line is 6-foot-4, 329-pound defensive tackle Ross Blacklock, who earned Big 12 Co-Defensive Freshman of the Year honors last season. The massive nose tackle demonstrated impressive athleticism for his size in his first playing season as a Horned Frog, recording 6.5 tackles for loss.

The leader of TCU’s linebacker corps is senior Ty Summers, who earned honorable mention All-Big 12 honors last season and has started 24 games over the last three years. Summers has recorded 271 total tackles and 17 tackles for loss in his Horned Frogs career, and could play a leading role for the entire defense in 2018.

TCU’s secondary is led by redshirt junior cornerback Jeff Gladney, who also earned honorable mention All-Big 12 recognition last season, and senior safety Ridwan Issahaku. Gladney had two interceptions for the Horned Frogs in 2017, including a pick-six; Issahaku also returned an interception for a touchdown, and tied for second on the team with 66 total tackles.

While the Horned Frogs return some explosive offensive playmakers, the strength of their team last season was their defense, as they led the Big 12 – a conference known for its high-scoring games – in both total defense (331.4 yards per game, 19th in the Football Bowl Subdivision) and scoring defense (19.0 points per game, 15th in the FBS).

The Horned Frogs will have to make up for the losses of players like Boesen, Howard, Texada and Orr, but returning players like Banogu, Blacklock, Summers, Gladney and Issahaku give them a chance to have a stout defense once again.

Like Ohio State, TCU opens its season with two games that it should be able to easily win – against Southern and SMU – which makes it likely that both teams will be undefeated for their primetime clash in Greater Dallas, and potentially both highly ranked, depending on how highly TCU begins the season in the polls and how many spots they able to climb before Week 3.

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On a pound-for-pound basis, Ohio State has a more talented team than TCU, so the Buckeyes should be favored going into their matchup with the Horned Frogs. But the Horned Frogs will be looking for a statement win that could position them as a national contender, too, and they appear to have enough talent on both sides of the ball – with Turpin providing game-breaking return ability on special teams – to give the Buckeyes a real test in their first marquee game of the year.