The 2017 college football season enters the last weekend of September with 24 undefeated teams remaining.
The ACC leads the way with five of those teams, and defending national champion Clemson travels to Virginia Tech in a battle of 4-0 teams next week. Duke (4-0) and Miami (Fla.) (2-0) play on Friday.
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Here's the breakdown for the rest of the conferences: American (4), Big Ten (4), Pac-12 (4) Big 12 (3), SEC (2), Conference-USA (1), MWC (1). With that in mind, here are five questions about the remaining unbeaten teams in the FBS:
Which unbeatens surprise you most?
Hold the basketballs. Duke and Wake Forest are part of the reason the ACC has the most unbeaten teams, and the Blue Devils and Demon Deacons have been impressive doing it.
Duke beat Northwestern and Baylor in nonconference play and took out the rival Tar Heels 27-17 on Saturday. They can put a firm grasp on the ACC Coastal race with a win against Miami (Fla.) on Friday. The Blue Devils played in the ACC championship game in 2014. Never underestimate David Cutcliffe.
Wake Forest, led by fourth-year coach Dave Clawson, could drop Florida State to 0-3 this week. The Demon Deacons survived a trip to Appalachian State in a 20-19 victory last week, and they play Clemson on Oct. 7. Quarterback John Wolford, who has 676 passing yards, 269 rushing yards and 11 total touchdowns, is going to get some attention as a result.
Who is your favorite Group of 5 buster?
The American Athletic Conference quad meet among South Florida, Central Florida, Navy and Memphis is going to be great. UCF hammered Maryland 38-10 and gets Memphis this week in a battle of hot coaches in Scott Frost and Mike Norvell.
South Florida continues to take care of business under first-year coach Charlie Strong, and Navy is business as usual with Ken Niumatalolo. It's good football, but can one of these schools go undefeated?
San Diego State of the Mountain West and UTSA in Conference-USA might benefit from those AAC schools picking each other off.
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Best regular-season matchup?
Michigan at Penn State on Oct. 21. The Nittany Lions averaged 496.5 yards per game on offense. The Wolverines allow 203.3 yards per game on defense. It's a strength-on-strength matchup of the best kind, and the “Whiteout” backdrop would be only part of the drama.
It's Jim Harbaugh and James Franklin. Rashan Gary chasing Trace McSorley. Ditto with Saquon Barkley and Devin Bush. Michigan's offense and Penn State's defense have time to improve before that one, but if they are unbeaten going into this game, it will be the most-watched primetime game of the regular season.
What about conference championships?
Imagine the following conference championship weekend each of these teams were 12-0:
ACC: Miami (Fla.) vs. Clemson
Big Ten: Penn State vs. Wisconsin
SEC: Alabama vs. Georgia
That would be the greatest conference championship weekend in college football history. Those would be de facto quarterfinal games in a lot of respects if Oklahoma and TCU lose in the regular season. Again, this potential scenario would hurt the Big 12, which added a championship game but features round-robin play in the regular season.
Of those potential matchups, however, it's not close. A 12-0 showdown between the Crimson Tide and Bulldogs — and between Nick Saban and protege Kirby Smart — would be off the charts.
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How many unbeaten teams reach playoff?
This last part is fantasy, because we have such a long way to go. One undefeated team has reached the College Football Playoff each of the last three seasons in Florida State (2014), Clemson (2015) and Alabama (2016). None of those teams won the national championship.
As for this season, we'll split the difference between Alabama and Clemson. At least one of those teams will reach the postseason with a perfect regular-season record, and the better bet is the Crimson Tide.
They made their presence felt with a 59-0 victory in their SEC opener against Vanderbilt. Here's a full breakdown on the remaining unbeatens in the FBS:
| TEAM | W | L | CONFERENCE |
| Alabama | 4 | 0 | SEC |
| Central Florida | 2 | 0 | American |
| Clemson | 4 | 0 | ACC |
| Duke | 4 | 0 | ACC |
| Georgia | 4 | 0 | SEC |
| Memphis | 3 | 0 | American |
| Miami | 3 | 0 | ACC |
| Michigan | 4 | 0 | Big Ten |
| Minnesota | 3 | 0 | Big Ten |
| Navy | 3 | 0 | American |
| Oklahoma | 4 | 0 | Big 12 |
| Penn State | 4 | 0 | Big Ten |
| San Diego State | 4 | 0 | Mountain West |
| South Florida | 4 | 0 | American |
| TCU | 4 | 0 | Big 12 |
| Texas Tech | 3 | 0 | Big 12 |
| Utah | 4 | 0 | Pac-12 |
| UTSA | 3 | 0 | C-USA |
| Virginia Tech | 4 | 0 | ACC |
| Wake Forest | 4 | 0 | ACC |
| Washington | 4 | 0 | Pac-12 |
| Washington State | 5 | 0 | Pac-12 |
| Wisconsin | 3 | 0 | Big Ten |
