CLEMSON — Underneath the offensive fireworks this season at Clemson, there has been a quiet undercurrent: the Tigers’ defense has changed from liability to an asset over the last six weeks.

Four games into the season, following the loss at Florida State, the Clemson defense was performing worse than it was a year ago under Kevin Steele. Clemson ranked 95th in total defense, allowing 443 yards per game. But as No. 11 Clemson (9-1, 6-1 ACC) prepares to face N.C. State (6-4, 3-3) at 3:30 p.m. Saturday (ESPN2 or ABC) Clemson has improved to 54th in the nation in total defense, cutting its yards allowed to 389 per game.

Clemson has allowed a modest 20.5 points per game during its six-game winning streak.

Yes, Clemson has faced few formidable offenses since losing to the Seminoles. But last season, Clemson struggled to slow just about every team not named Virginia Tech.

Clemson defensive coordinator Brent Venables said there is real improvement occurring, that the gains are not just the product of playing a weak schedule.

“We’re in a much more consistent place. We’re not hurting ourselves,” Venables said. “Nothing drives you more bananas and disgusts you more than when you are your own worst own enemy. We are not doing the same things we were earlier in the year. It’s about us being in the right spots. Against Auburn, they ran an (isolation run play) and our fit player gets 25 yards deep instead of five yards deep...(On another play) we had a post player that should been 25 yards deep in the middle of the field and they score a 50-yard touchdown because he’s eight yards from the line of scrimmage. We had no chance.

“Our positioning is better, we’re tackling better as a result of good position. We have good eye control. Better discipline. Little things make a big difference.”

Clemson coach Dabo Swinney said Clemson had a season-low two mental errors against Maryland.

Perhaps most impressive is Clemson held Maryland to 1 of 13 on third-down conversations, a stat that plagued the defense in the past.

“The thing that jumps out at you is how much we’ve improved fundamentally,” Swinney said.

Improvement has not come from making wholesale lineup changes.

Just one starter — middle linebacker Stephone Anthony — has been replaced for performance reasons. The improvement is from more time learning under Venables and more time for Venables to learn his players and staff.

“It’s a process,” Venables said. “You have to find out what these guys can do, what they’re not so good at, what stresses them. You have to have some failures along the way. How we are going to operate as a defensive staff? What can we do? What we can’t we do?

“We’re not perfect by any stretch, but it’s obviously good to see that maturation.”

Sweet trip? projected Clemson will play No. 4 Alabama in the Sugar Bowl in its latest forecast. If that matchup were to occur, it would become one of the hottest bowl tickets in Clemson history.

Polling data

Despite a 35-point win over Maryland on Sunday, Clemson fell from No. 10 to No. 11 in the Associated Press poll. Texas A&M jumped from 15 to 9 after beating Alabama. Clemson remained No. 8 in the coaches poll and jumped from 13th to 11th in the BCS Standings.

Dabo said it

Swinney on defensive end Vic Beasley: “If we put 15 pounds on him, he’s going to be a creature running around out there. He has a really special skill set.”