The fifth week of the college football season offers arguably the best lineup of games since the opening weekend. With so many top 10 teams facing each other, this week could provide some clues on which teams have legitimate College Football Playoff aspirations.
No. 3 Louisville at No. 5 Clemson.
This weekend features two other matchups of top 10 teams as No. 7 Stanford visits No. 10 Washington on Friday night and No. 8 Wisconsin plays at No. 4 Michigan on Saturday.
But the Atlantic Coast Conference showdown offers the most intrigue. The winner takes command of a loaded Atlantic Division that also features No. 12 Florida State, which already got blown out at Louisville two weeks ago.
Louisville is averaging 63.5 points to lead all Football Bowl Subdivision programs.
Clemson allows just 11 points per game and is tied for fifth nationally in scoring defense. The Tigers also have won 18 straight regular-season games and a school-record 18 straight home games.
That Louisville-Clemson showdown also could have major Heisman Trophy implications.
Clemson quarterback Deshaun Watson entered the season as one of the Heisman favorites, but his thunder has been stolen a bit by Louisville quarterback Lamar Jackson's sensational September. Watson could reassert himself as a Heisman front-runner by outplaying Jackson in a Clemson victory.
''I know (Watson's) the best player in the country,'' Clemson receiver Ray-Ray McCloud said. ''For him to go out there against someone who supposedly is the best player in the country as well is just going to get him to a whole other level.''
NUMBERS TO KNOW
4 - The number of wins for undefeated Wake Forest heading into Saturday's game at North Carolina State. The Demon Deacons haven't won more than four games in a season since going 5-7 in 2012.
8-4-2: Wisconsin won 30-6 last week over No. 17 Michigan State, which was ranked eighth at the time of their meeting. The Badgers visit No. 4 Michigan this week. After taking next week off, they host No. 2 Ohio State on Oct. 15.
12-1 - No. 11 Tennessee has 12 fumbles this season but has lost only one of them.
35 - Oklahoma has won 35 consecutive regular-season games following a regular-season loss. The Sooners haven't lost consecutive regular-season games since October 1999. The Sooners try to continue that streak Saturday when they visit No. 21 TCU after losing to Ohio State in their last game.
OFF THE RADAR
Memphis had to replace its coach and quarterback as Virginia Tech hired away Justin Fuente and the Denver Broncos drafted Paxton Lynch in the first round. But the new-look Tigers have done just fine so far, as they have outscored opponents 155-27 in the first three games of Mike Norvell's coaching tenure.
The Tigers face a much tougher test this week at No. 16 Mississippi. The Rebels are seeking to avenge the 37-24 loss at Memphis last season.
''We went up there and got embarrassed last year,'' Ole Miss defensive lineman John Youngblood said. ''I don't think we prepared well, and we didn't have our mindset good enough going into the game.''
COACH IN NEED OF A WIN
Notre Dame coach Brian Kelly's decision to bring back Brian VanGorder as defensive coordinator this season backfired when the Fighting Irish staggered to a 1-3 start while allowing 33.5 points per game.
Kelly fired VanGorder on Sunday, the day after a 38-35 home loss to Duke. Greg Hudson is taking over the defense on an interim basis.
Notre Dame opened the season ranked 10th and has a quarterback (DeShone Kizer) being mentioned as a potential No. 1 overall draft pick, but the Irish will struggle to finish above .500 if they don't fix their defense.
Kelly and the team try to turn things around Saturday when Notre Dame faces Syracuse's up-tempo attack at MetLife Stadium in East Rutherford, New Jersey.
Online: The AP's college football page: http://collegfootball.ap.org