CLEMSON, S.C. >> Clemson's rebuilt, young defense has passed its earliest tests to keep the fifth-ranked Tigers undefeated. Now, they face perhaps the biggest challenge of the season in slowing the remarkable roll of No. 3 Louisville and quarterback Lamar Jackson.

"You can do everything right and still be wrong" when it comes to Jackson, Clemson defensive coordinator Brent Venables said.

Louisville's opponents understand what Venables means. The third-ranked Cardinals (4-0, 2-0 Atlantic Coast Conference), who face No. 5 Clemson (4-0, 1-0) on Saturday night, lead the Football Bowl Subdivision with 63.5 points a game. Jackson has accounted for 25 touchdowns, 12 of them running.

Jackson is the Heisman Trophy front-runner through the first third of the season.

"We know how much of a playmaker and how he is an elite talent," Clemson linebacker Ben Boulware said. "But we are up for the task."

That was a huge question coming into the season as the Tigers faced life without seven defensive starters from last year's ACC champions, six who were chosen in last spring's NFL draft. So far, so good. The Tigers have allowed just 218 yards a game, the country's third best total.

Christian Wilkins and Clelin Ferrell have filled in at defensive end for NFL draft picks Shaq Lawson and Kevin Dodd, who finished 1-2 nationally in tackles for loss last year.


Freshman Dexter Lawrence, a January enrollee, moved into the starting lineup in week two and has plugged up the middle at nose tackle.

Boulware said Clemson's defense has to keep Jackson in the pocket and not let him make plays on the move. "It's very important for our (defensive) line to get pressure and win their matchups," he said.

Jackson has been adept at seeing the defensive plan and figuring out a way to beat the opposition on the ground or in the air. He has thrown for 1,330 yards and 13 TDs this season and rushed for 526 yards. Jackson is the first FBS quarterback in 10 years to have two games in a season where he's accounted for seven touchdowns .

"It's really kind of freaky when you look at the numbers that they put up," Clemson coach Dabo Swinney said. "It would be hard to put up these numbers in a video game."

Venables hasn't spent much time on his X-Box lately, but is among the best in the country at attacking and limiting an opponent's strength. Last week in 26-7 victory at Georgia Tech , the Tigers held the Yellow Jackets relentless, triple-option attack to 124 yards total.

"Coach V is a football guru," Boulware said of Venables. "He knows the ins and outs of that type of offense. So it starts with him and ends with us."

For Jackson, things typically end in the end zone — which Louisville knows it will need at sold-out, ultra-loud Death Valley.

"It's really important to get off to a good start because playing away at a place like Death Valley, it's good to steal the momentum early so you get the crowd out of it early and just play the game instead of focusing on the crowd," Cardinals receiver Jaylen Smith said.

The crowd may have rattled the Cardinals in their only other trip to Clemson two years ago. Louisville had a first-and-goal at the 8 in the final minute, yet inexplicably spiked the ball on third down and was forced into a fourth down pass that was knocked down by Clemson defensive tackle DeShawn Williams in a 23-17 victory.

Louisville coach Bobby Petrino understands the Tigers will be active and physical up front once again.

"Probably be the biggest defensive line that we've played this year," he said.

Jackson's play this season has overshadowed the solid showing of Clemson quarterback Deshaun Watson, the defacto Heisman favorite entering the season. Boulware believes facing Watson's skillset in practice gives the Tigers an edge in shutting down Jackson.

"They are very similar and pretty much identical," Boulware says. "So getting to go up against Deshaun all throughout fall camp the past three years is pretty good preparation for Lamar Jackson."