SAN ANTONIO -- Chris Duhon stalks his opponent, swiping at the ball when he sees a screen out of the corner of his eye.
His ribs are sore, bruised from a fall in a game two weeks ago. He could go around and avoid impact, but he's not going to let up. He fights over the screen - wincing with the glancing blow - and stays with the ballhandler.
All season, Duhon's dogged determination has been the motor that powers Duke's aggressive defense. Now, after straying briefly from that shut-you-down mind-set late in the season, the Blue Devils are back to playing the defense that coach Mike Krzyzewski loves heading into Saturday's national semifinal game against Connecticut.
"We've been a really good defensive team all year," Krzyzewski said. "We were playing great defense during (the winning streak). Then, I think we let up because we started to score more. But in the NCAA tournament we've played very well defensively."
The Blue Devils (31-5) have held opponents to 40 percent shooting and 65 points per game this season. Duke has also averaged a school-record 6.6 blocks and forced 17.2 turnovers per game.
During an 18-game winning streak, Duke's defense overwhelmed opponents and carried the Blue Devils to a midseason No. 1 ranking. But the Blue Devils wavered, losing four of 10 games heading into the NCAA tournament.
They sure seem back to form. In tournament wins against Alabama State, Seton Hall, Illinois and Xavier, they allowed 62 points per game and 39 percent shooting.
Duke's staple all season has been pressure man-to-man defense. When it's working well, the Blue Devils get hands in passing lanes to force turnovers, fueling a potent transition game.
It all starts with Duhon, a freshman on Duke's 2001 NCAA championship team. The 6-1 senior typically chases the opponent's top perimeter player, and hasn't let his sore ribs suffered in the Atlantic Coast Conference tournament slow him.
He never wants to let his opponent breathe, partly because the injury makes it hard for him to do the same thing.
"I'm just trying to help my team out as much as possible right now," said Duhon, who has worn a protective wrap under his jersey. "I take pride in my defense. I just want to go out and try to help my team win."
Duhon held the Illini's top scorer, Deron Williams, to seven points on 3-for-13 shooting in the third round, then alternated on Lionel Chalmers and Romain Sato of Xavier. The duo had combined for 41 - Sato had 27 - in the third round against Texas, but had 27 points on 8-for-26 shooting against Duke in the Atlanta Regional final.
"Each of the kids he guarded went from hot to cold," Krzyzewski said.
On the inside, the rugged 6-9 Shelden Williams has blocked nine shots, tying UConn All-American Emeka Okafor for tops in the tournament. Duke also has 6-10 reserve Shavlik Randolph - who has blocked four shots in the last three games - and Luol Deng, a 6-8 freshman with the versatility to defend on the wing or inside.
"You'd have to prepare for every player they have," Huskies guard Ben Gordon said. "They have pressure defense. You can't prepare for just inside or outside."
The Blue Devils' defense has overcome a drop in offensive production. After averaging 93 points in the first two rounds, Duke averaged 69 points in its next two wins.
"I've been told that offense wins games and defense wins championships," junior guard Daniel Ewing said. "Even if the offense is not going for us, as long as we keep playing good defense ... we're going to score some buckets. Somehow, someway, we're going to get some points."