No. 11 Clemson lost its first ACC game of the season, losing at home to Louisville 33-21.

Isaac Brown ran for a 45-yard touchdown after the Cardinals repelled a Clemson onside kick attempt to tie the game with 5:50 left in the fourth quarter.

After Phil Mafah scored a three-yard TD to make the game 26-13, Clemson opted to kick an extra point rather than attempt a 2-point conversion to cut the lead to 11 points. That decision made more sense when the Tigers attempted an onside kick, but Louisville recovered. (The replay appeared to show that Clemson had two players offside anyway, but that didn't matter.)

Fans threw objects onto the field in protest, but after the brief delay, Brown delivered the dagger with his touchdown run.

The Tigers' passing game had no answer for the Louisville defense, yielding 219 yards. Quarterback Cade Klubnik completed 32 of 55 passes for 219 yards and a touchdown, but the majority of those yards came after the game was out of reach. TJ Moore had 63 yards on five catches.

Mafah had a monster performance running the ball, gaining 171 yards on 30 carries. (Klubnik added 43 yards on 12 carries.) But his two touchdowns came too late.

After falling behind 26-7, the Tigers had to throw the ball to catch up. But Clemson and offensive coordinator Garrett Riley didn't show much urgency by increasing the tempo and trying to score quicker.

Brown finished the game with 151 yards rushing on 20 carries for Louisville, while Chris Bell added 47 yards on his only rush. Quarterback Tyler Shough threw for 156 yards and completed 17 of 32 passes. Ja'Corey Brooks led the Cardinals in receiving with 49 yards on four receptions. And Brock Travelstead kicked four field goals, his longest of 49 yards.

The loss drops Clemson to third place in the ACC behind Miami and SMU, both 5-0. Pittsburgh is right behind the Tigers at 3-1 after suffering its first conference loss to SMU.