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North Carolina coach Roy Williams waited until mid-February to shorten his bench and rely largely on a small lineup. It remains to be seen whether it was a short-term move or something the Tar Heels will use through the final weeks of the season.

The Tar Heels spent the days leading up to their game at No. 2 Duke working to turn that occasionally used four-guard unit into the focus of their attack. The plan worked well enough to keep North Carolina in the game the entire night in one of college basketball's most hostile settings and gave the Tar Heels a jolt that had been missing so far in Atlantic Coast Conference play.

"I think we do a better job of spacing the floor when we have four guards on the court because spacing has been an issue for our offense for a lot of the year," freshman point guard Marcus Paige said after Wednesday night's 73-68 loss. "But when we have four guards, we're able to spread the floor, get driving lines and (James Michael) McAdoo has more room to operate, too. It's an interesting lineup we can play with."

Williams moved P.J. Hairston into the starting five against the Blue Devils alongside regular starters Paige, McAdoo, Dexter Strickland and Reggie Bullock. Hairston's only start this year came in December against UNLV when Bullock was out with a concussion. He had played stretches as the 4-man for the Tar Heels before, but this time, he was on the court almost the entire night.

It was North Carolina's sixth starting lineup this year.

Hairston, a 6-foot-5 sophomore guard, matched his career-high with 23 points and had eight rebounds — seven offensive — in 34 minutes, though he struggled from the outside and finished just 1-for-7 from 3-point range. Still, Hairston's presence allowed the Tar Heels (16-8, 6-5 ACC) to keep up with the Blue Devils' outside shooters defensively most of the night.

It also helped the Tar Heels get off to a strong start, jumping to a 7-2 lead and leading by 10 on Bullock's third 3-pointer with 7 minutes left in the first half.

"They started a different lineup and they really went away from all the stuff they usually do in trying to run it down our throats," Duke coach Mike Krzyzewski said. "... Those two kids, Bullock and Hairston, are two of the best shooters in the country and they put a lot of pressure on you."

Compare that to the past five games, when they fell behind in the opening minutes — including 10-0 at home to offensively challenged Virginia Tech — each time with a more traditional starting lineup that had 6-10 defensive-minded sophomore Desmond Hubert in the middle.

Bullock finished with a team-high 36 minutes; Hairston, Strickland and McAdoo played 34; Paige played 30 and sixth man Leslie McDonald — yet another guard — played 20 minutes. No other Tar Heel played more than 4 minutes.

UNC had played at least eight players for double-figure minutes in 21 of 23 games before Wednesday's trip to Cameron Indoor Stadium and never fewer than seven.

Hubert had played at least 10 minutes in every game for the past two months, but made little more than a cameo (1 minute) against the Blue Devils. Meanwhile, freshman forward Brice Johnson (4 minutes) and freshman guard J.P. Tokoto (3 minutes) each logged season-low totals.

Strickland said the shortened rotation forced UNC's offense to find a rhythm.

"You understand the comfort zone they like to be in — Reggie coming off screens a certain way, you know (Marcus) is going to drive and kick it out," Strickland said. "You get a feel and you get in your zone and not having all these subs — he does this, he does that — you know what to expect from the player you're playing with."

The Tar Heels started the year at No. 11 and reached ninth in Top 25, only to start 0-2 in the ACC and fall out of the national rankings. UNC's most glaring problem has been replacing four NBA first-round draft picks from last year's team, leaving behind a team a bit thin up front but returning plenty of experienced guards.

Williams certainly took advantage of them against Duke. He just wasn't saying whether he'd stick with the small lineup against Virginia and beyond.

"We started to make that change four or five games ago," Williams said. "I may start five different guys Saturday."