The biggest X-factors for the college football top 25

Grayson McCall. The redshirt freshman quarterback is a major reason the Chanticleers are the lone undefeated team in the Sun Belt and ranked for the first time in school history. The versatile McCall has thrown for 930 yards with 11 touchdowns and one interception while also rushing for 184 and three scores. McCall is definitely someone to keep an eye on, even as more Power 5 schools begin their seasons.

Physicality. This sounds like a made-up word that football types like to throw around. But it's becoming a growing talking point for the Trojans, who await the start of their 2020 season. It's about winning the matchups on the line of scrimmage -- both sides of the ball -- and putting effort into every play. Setting the tone with a big hit, a proper tackle or just making their overall collective, physical presence felt.

Forcing mistakes. Through the first three games of the season, N.C. State forced just one turnover. However, the Wolfpack have forced seven in the last two contests -- including three interceptions in each. Is this the start of a trend? If so, N.C. State would surely take it. It's defensive unit is already a confident group and when it's forcing turnovers at a consistent rate, the sky might be the limit.

Run defense. Marshall has scored at least 35 points in all but one game this season. However, a key to its strong start to this unique campaign has been the play of the Thundering Herd defense. That unit has allowed 38 total points, and more impressive, an average of 2.4 rushing yards per carry. In last weekend's 35-17 win at Louisiana Tech, Marshall yielded just seven yards on the ground.

Keep control. Of the ball. And, thus the clock. Last season, Minnesota ranked fourth nationally with a 34:12 average in time of possession. The Gophers had a relatively balanced offense during the 2019 season, and that obviously becomes imperative right of the gate this year. Minnesota opens at home against No. 18 Michigan, then plays consecutive road games at Maryland and Illinois.

Handle with care. The Wildcats are surprise co-leaders in the Big 12 at 3-0. One big reason for Kansas State's success is because it's only committed one turnover this season. That came in the Wildcats' most recent contest, a 21-14 win at TCU on Oct. 10. Their only turnover is an interception, so the fact they've been able to keep the ball off the ground has been a big deal.

Keep on runnin'. Offensive success for the Hokies is pretty simple: keep running the football. Entering this weekend's play, Virginia Tech ranks second in the nation averaging 312.0 yards on the ground. Khalil Herbert has been the star of the show thus far, rushing for 593 yards with five touchdowns.More impressive, Herbert is averaging 9.6 yards per carry, which also ranks among the nation's best.

Quarterback play . Spoiler alert. The Wolverines won't be the only team among those in the Top 25 play who must get a consistently strong effort from the quarterback position. Joe Milton is the only quarterback on Michigan's current roster who has game experience. He's expected to make his first start for the Wolverines this weekend at No. 21 Minnesota. Since Jim Harbaugh's become Michigan coach, quarterback inconsistency has been an issue. 

Confidence. It's back.Or at least so it appears. After opening the season with a 31-14 home loss to upstart Louisiana, the Cyclones looked as it they were headed for another underachieving campaign. Instead, Iowa State has regrouped to turn things around by pulling out a win at TCU and beating Oklahoma and Texas Tech at home. The collective belief is back and finally the Cyclones might be living up to the hype.

Focus. Sounds simple enough. In fact, that's an X-factor for every program in the country. But, it seems SMU really needs to keep its own over the next four weeks. Things won't be easy for the Mustangs, who host No. 9 Cincinnati this weekend and then face a Navy squad that's unbeaten in American Athletic Conference play at the moment. After that, road dates at Temple and Tulsa await, so SMU has its work cut out.

Quarterback . We know the Badgers are going to pound the football on the ground. That's always the case and will be again. However, big things were expected from quarterback Jack Coan (2,727 yards, 18 touchdowns, 151.8 passer rating in 2019), but he's out indefinitely with a foot injury. Redshirt freshman Graham Mertz appears set to get the first crack at filling in for Coan, so we'll see how things play out.

Stop the run. The Tar Heels fell back down to earth with last weekend's loss at Florida State. If Carolina is to bounce back and start another winning stretch, it needs to fare better against the run. The Tar Heels allowed 108 yards in their first two games against Syracuse and Boston College, but yielded 501 versus Virginia Tech and the Seminoles. If they can right that ship, things should once again be rosy.

Joe Moorhead . The Ducks' new offensive coordinator lost plenty of big-time talent on that side of the ball from last season. Starting with quarterback Justin Herbert. The former Mississippi State head coach is a veteran within the college football universe, and the Ducks are the class of the Pac-12 heading into the league's season. As long as he makes the most of the talent Oregon does have on offense and not ask too much, conference expectations should be met.

Be prepared . Thanks to Zach Wilson (1,641 yards, 12 TDs, one interception, 78.7 completion percentage), the Cougars have reason to believe it can run the table on this condensed season. BYU has five games remaining, and its two biggest tests come at Boise State on Nov. 6 and versus San Diego State to conclude its regular season. As long as the Cougars stay humbled, determined and prepare themselves, an undefeated run is a reality.

D'Eriq King. It's a wonder what good, consistent quarterback play can do for the collective confidence of an entire team. That's what the Houston transfer has brought to the Hurricanes. King has thrown for 1,076 yards with 10 touchdowns and four interceptions while also rushing for 273 yards with two scores. Now, King can get a little over-aggressive at times, but the 'Canes feel good about themselves because they have a quarterback who feels the same about his own abilities.

COVID-19: The coronavirus has infiltrated the SEC, and the Gators are in the midst of a breakout. How they overcome it, and if coach Dan Mullen will take it serious and not harp about how we wants The Swamp completely filled with fans will determine the fate of the program's season. The Gators are not scheduled to play again until Halloween, so perhaps things will settle down within the program and health will take prevalence over football.

Stay sharp. Plagued by COVID-19 issues, the Bearcats have not played since Oct. 3, when they beat South Florida. They are slated to be back in action against No. 16 and undefeated SMU this weekend. That's a long time during the middle of the season to go without a game, so it will be interesting to see if any rust has accumulated during this downtime. Especially since more tough tests against Memphis and Houston follow after visiting the Mustangs.

Making up for no more Micah . Linebacker Micah Parsons was arguably the best defensive player in the country last season. Unfortunately for Nittany Lions fans, Parsons opted out of 2020 season and then decided to stay gone when the Big Ten decided to return to action. Penn State still has plenty of defensive talent to be among the best squads in the nation, but it will be interesting to see if losing Parsons will have any negative effects. 

Isaiah Spiller . It's easy to point to quarterback Kellen Mond or maybe a receiving corps that must overcome injuries. But, Spiller has been relatively strong enough to be counted on every game to produce and keep the offense moving. He's rushed for 430 yards, topping 100 in three games, and scored all four of his touchdowns in his last two weeks. Spiller's 174-yard effort against Florida was an eye-opener.

Defense. Pretty straight forward with this one. The Cowboys have allowed 27 points through three games. However, that's come against Tulsa, West Virginia and Kansas. Now things get rough with No. 17 Iowa State, Texas, 20th-ranked Kansas State and Oklahoma on tap in consecutive games. That's a tough stretch, and we should get a better idea of just how good Oklahoma State's defense really is.

Defensive line . There aren't many glaring concerns when it comes to the Buckeyes. If we want to get picky about one area where a game or two might be determined, it's on the defensive front. Chase Young is gone and Zach Harrison (3 1/2 sacks last year) has the best chance of being the unit's next breakout star. Otherwise, others will need to step up within a Big 12 known for wanting to pound the football.

Alabama. The Crimson Tide continue to be Georgia's white whale. Why does that matter after the Bulldogs blew another lead in last weekend's 41-24 loss to Alabama? Because, let's say Georgia wins the SEC East Division and Alabama wins the West. They would again meet in the league title game with a spot in the College Football Playoff likely on the line. Depending on what's going on elsewhere around the country, Georgia's playoff fate could be on the line with the Tide standing in the way -- again.

Ian Book. In the midst of his fourth season, is it possible to say the verdict is still out on Book? Perhaps. But, many would agree that the key to Notre Dame's success is Book. After throwing 34 touchdowns last season, Book has just three in four games this year. His 61.7 completion percentage is below his career number and he did not look particularly sharp in last weekend's 12-7 win over Louisville.

Pass defense. Granted, the Tide have no problem with high-scoring affairs and when they get out to a big lead, opponents throw the ball to make things interesting. Still, Alabama has allowed eight passing touchdowns this season and two quarterbacks to throw over 330 yards. Now, Alabama has recorded five interceptions, so it can be opportunistic at times. If it can be a little more consistent in this area, Alabama can be even more dominant than it appears.

Myles Murphy. There is so much talent on both sides of the ball for this Tigers team. But, Murphy is worth singling out because the freshman end is probably going to be the program's next big defensive star. He leads the team with 3 1/3 sacks and has recorded 6 1/2 tackles for loss. In the case of the Clemson defense, it's not about rebuilding, but reloading. Murphy is pushing his way to top of the arsenal and may soon become the face of one of the country's best defenses.