Lessons from Week 4 of the College Football Playoffs: Clemson and Utah soar as USC tumbles

There were no real surprises in Week 4 of college football, but we did learn more about the teams that should be in the running for the College Football Playoff at the end of the year. Some teams aren't out of the running yet, while others aren't as dominant as expected, and the pool for a spot seems much larger than it was a week ago.

Here are five lessons from Week 4 related to the CFP:

1. Clemson is not finished yet

It seemed like the college football world had moved on from Clemson after its 34-3 opening loss to Georgia, but reports of the Tigers' demise may have been greatly exaggerated. Since that loss, Clemson has posted a 66-20 win over Appalachian State and a 59-35 win over NC State on Saturday.

Yes, the Wolfpack started with a true freshman quarterback, but that didn't matter. Clemson led 28-0 in the first quarter and the game was over shortly after it began. The Tigers used quarterback Cade Klubnik's legs a little more, which was evident in his 55-yard touchdown run. Running back Phil Mafah left the game briefly with an apparent shoulder injury, but returned and immediately scored a 38-yard touchdown run. He finished the game with 107 yards on seven carries.

Clemson doesn't need to be a top-four team to get into the CFP. The Tigers just need to win the ACC. The Clemson we've seen in recent weeks looks like a team that could get an automatic or maybe even an at-large spot. Clemson hosts Stanford next week and then travels to Florida State. The Tigers don't play Miami in the regular season and get Louisville at home, making for a manageable schedule.

Much of the hype surrounding the Volunteers this season has been about their quarterback, but Saturday's 25-15 win at No. 15 Oklahoma was a different approach. The Vols knew Oklahoma couldn't move the ball against their defense, and they played conservatively in the second half to secure a win without any style points, and that's OK. (Oklahoma's defense also seems very good, so don't play too risky.)

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Iamaleava was good, completing 13 of 21 passes for 194 yards and a touchdown, but the Vols ran the ball 52 times overall. Oklahoma quarterback Jackson Arnold was so abysmal with three turnovers that he was benched in the first half for true freshman Michael Hawkins Jr. Tennessee led 19-3 at halftime and played the second half knowing the Sooners weren't going to catch up.

Oklahoma totaled 222 yards and 1.1 yards per carry, including sacks. This Tennessee defense is really good, and that's why the Vols are in prime CFP position.

3. USC missed the chance to make an early statement

The Trojans have improved, especially on defense. That's obvious. There's again reason to be pleased with the direction of the program under Lincoln Riley. But Saturday's 27-24 loss at Michigan was a missed opportunity. USC came back from a 14-0 deficit to take the lead in Ann Arbor, but last year's poor tackling showed up at the worst possible time, as the Wolverines ran for a game-winning touchdown in the final seconds.

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Michigan threw for just 32 yards. The Wolverines had fewer than 20 yards in the second half before their final drive. But USC threw a costly pick-six and the defense stumbled at the end. A win would have put USC at 3-0 with wins over LSU and Michigan and a doable path to a CFP berth. Instead, the loss means the Oct. 12 home game against Penn State could be a must-win for Big Ten championship game hopes. It also means USC may be able to afford just one more loss to have a chance at an at-large bid. This would have been a good win to have in the bag.

Utah wide receiver Dorian Singer caught seven passes for 95 yards in the Utes' win over Oklahoma State. (William Purnell / Imagn Images)

4. Utah took early control of the Big 12, but can it hold on?

Utah's road game against Oklahoma State to open Big 12 play was a game that would provide an early advantage in Big 12 play among the favorites. Utah secured that advantage, winning 22-19 and holding onto its lead after taking a 22-3 fourth quarter lead. The Utes' defense was strong as expected, holding the Cowboys to 285 yards and running back Ollie Gordon II to just 42 rushing yards.

Quarterback Cam Rising missed another game because of a finger injury on his throwing hand. Receiver Dorian Singer said earlier in the week that Rising would play. The betting odds swung from -2.5 for Utah to -2.5 for Oklahoma State on Wednesday night, seemingly indicating he would not play. Rising eventually warmed up but did not play. Backup Isaac Wilson completed 17 of 29 passes for 207 yards, one touchdown and two interceptions, along with 41 rushing yards. It was enough for the win, and his play has been better in recent weeks, but Utah probably needs Rising healthy if it wants to win the Big 12 and get into the CFP.

Other preseason favorites in the Big 12 include Kansas at 1-3, Arizona at 2-1 and Kansas State at 3-1 after a late loss at BYU. The Utes play Arizona next week and three of their final four games are against BYU (4-0), Iowa State (3-0) and UCF (3-0).

5. The fifth CFP place for the Group of 5 is again completely open

It didn't take long for the good feeling to fade after a few Power 4 upset wins. Memphis lost 56-44 at Navy, one game after beating Florida State. Northern Illinois lost in overtime to Buffalo, one game after beating Notre Dame. Toledo lost to Western Kentucky, one game after beating Mississippi State. It was a reminder that it's difficult for any G5 team to go undefeated against G5 teams with a similar talent level (or a unique style, in Navy's case).

Boise State also suffered a loss to Oregon. UNLV, which is at the top of the coaches' poll, is currently undefeated, and James Madison, which has been mediocre for two weeks, beat North Carolina in a stunning 70-50 game. And then there's Liberty, which now leads 4-0 after pulling away late to beat East Carolina 35-24.

Most of the early favorites for first place in the G5 have lost a game or two, leaving the race wide open as conference play begins, but the question of the Undefeated Liberty continues to loom over everything.

(Top photo of Cade Klubnik and Phil Mafah: John Byrum / Icon Sportswire via Getty Images)