HOUSTON — The changes weren't as radical as Vincent Van Gogh forsaking his brushes to spray paint graffiti on highway overpasses, or Luciano Pavarotti fronting for Rage Against The Machine.

But when guard Elliot Williams announced in June he was transferring from Duke (and ultimately to Memphis), it became immediately obvious that the Blue Devils would have to change.

Playing with the old Duke staples - an attacking, fast-paced style and full-court defensive pressure - no longer was possible.

The departure of the jet-quick Williams left the Blue Devils with only two true guards on scholarship in Jon Scheyer and Nolan Smith. And although Andre Dawkins hustled through summer school courses and enrolled a year early as a freshman to add depth, speed was not going to be the strength of this team.

But the Blue Devils possessed one quality they've almost never had under coach Mike Krzyzewski. They had five players 6 feet 8 or taller who were ready to play significant roles.

So Krzyzewski changed his system to fit them and reconstructed Duke into one of the nation's top teams.

The bigger, tougher Blue Devils earned a No. 1 regional seed in the NCAA tournament after capturing a share of the ACC's regular-season title and winning its second straight ACC tournament

The only ACC team left standing in the NCAA tournament, the Blue Devils (31-5) face fourth-seeded Purdue (29-5) tonight in the South Regional semifinals in Houston (9:57 p.m., WRAL, WNCT).

A win tonight would give them their deepest run in the NCAA tournament since 2004, when they reached the Final Four. It also would surpass the accomplishments of last year, 2006 and 2005, when Duke fell in the regional semifinals each time.

"We're ready to go past that," junior guard Nolan Smith said. "We're ready to do what we've got to do defensively and rebounding-wise to do that."

It was the middle of the season just two years ago when Duke was being celebrated for a new scheme Krzyzewski and his staff had learned while working with the U.S. National Team and then-Phoenix Suns coach Mike D'Antoni.

Fanning out four and sometimes five 3-point shooters along the perimeter and opening up driving lanes, the Blue Devils won 28 games with a fast-breaking system in 2007-08. The current system, however, couldn't be more different.

A big change

Junior Kyle Singler, who played a lot of minutes at center when he was a freshman, has moved out to "small" forward at 6 feet 8. The Blue Devils have rotated four big guys at two true low-post positions in 7-1 Brian Zoubek, 6-8 Lance Thomas and 6-10 brothers Mason and Miles Plumlee.

"I like what he's done with his size," Purdue coach Matt Painter said of Krzyzewski. "He throws those bodies at you, and they keep coming in there."

Past Duke teams that possessed an abundance of speedy guards would pressure opponents all over the court, constantly playing in the passing lanes in hopes of forcing turnovers that would lead to fast breaks.

The current Blue Devils, though, play quite differently on defense.

"Most people, except for the more astute observers, wouldn't think they've changed their defense much this year," said ESPN analyst Jay Bilas, a former Duke player and assistant coach. "But they have."

The current Duke team doesn't often use full-court pressure, opting instead for its guards to stick to the opposition like glue in the halfcourt.

The objective is to force smaller opponents to attempt difficult shots over the top of Duke's tall defenders (at 6-5, even Scheyer is tall for a shooting guard).

As a result, Duke's opponents are shooting just 40.2 percent from the field, the lowest mark since 2004-05.

Positioning themselves between the shooter and the basket also leaves Duke in excellent rebounding position after the opponent fires up an errant shot.

Bilas said that when he played at Duke in the 1980s, Blue Devils low-post defenders usually played three-quarters of the way in front of opponents.

When the shot went up, that meant Duke's big guys were three-quarters of the way behind, which put them at a disadvantage when they rebounded.

"One of the reasons Duke hasn't been a good rebounding team over the years isn't because they don't have good rebounders," Bilas said. "It's because of the defense they played. Think about it. If you're going to be out in a passing lane, you're going to be 50-50 when a shot goes up, [so] it's not going to be as easy. You're going to give them more offensive rebounds."

The new strategy to take advantage of Duke's size has helped the team post a season rebound margin of plus-6.1, its best mark since the Elton Brand-led team of 1998-99.

More flexible

Early in his coaching career, Krzyzewski said, he wasn't as flexible with his system. But he said he became more open to change after learning from coaching legends such as Bob Knight, Pete Newell and Hank Iba,

"They stressed, 'Don't try to be like anyone else, and always try to adapt to your personnel. Don't try to force the personnel to always adapt to you,' " Krzyzewski said. "And that made sense to me, and that's kind of how we try to do it."

Krzyzewski is hardly the only coach to change his system over time. Purdue underwent its own major makeover after 6-9 forward Robbie Hummel suffered a season-ending knee injury Feb. 24.

The Boilermakers now play a four-guard lineup, having replaced Hummel with 5-9 Lewis Jackson.

"There's nothing in the manual [for] when you lose a guy like Robbie Hummel," Painter said. "You've got to do your best with the guys you have."

That's what Krzyzewski has done with this Duke team. He's even made some in-season tweaks, using more motion offense Feb. 4 against Georgia Tech to take advantage of Singler's skills and inserting Zoubek into the starting lineup Feb. 13 against Maryland

Principles such as sharing the ball and communicating on defense probably never will go out of style at Duke, so long as Krzyzewski is coaching.

But when next season comes, there's a good chance the Blue Devils' system will undergo significant changes again, perhaps returning to a faster pace. Seniors Zoubek and Thomas, the team's slowest starters, will be gone. The more athletic Plumlees probably will be starting.

Speedy freshman point guard Kyrie Irving will be able to push the ball in transition more along with Smith, the fastest player on this year's team. Associate head coach Steve Wojciechowski wouldn't speculate on how Duke will play next season.

But it would be only natural for Krzyzewski to be shake up the system again.

"I think it keeps it fresh and exciting for him as well, because we've won with a lot of different styles," Wojciechowski said. "This team is not a prototypical team, but we've won. And it's been a fun group to coach and figure out how to win with the guys you have."

ktysiac@charlotteobserver.com or 919-829-8942