CHAPEL HILL, N.C. - North Carolina didn't put on much of a crowd-pleasing show to celebrate its return to No. 1.

North Carolina's Tyler Hansbrough, center, drives between Florida State's Ryan Reid (42) and Jordan DeMercy (2) during the first half of a college basketball game in Chapel Hill, N.C., Tuesday, March 4, 2008. (AP Photo/Gerry Broome)

Tyler Hansbrough had 20 points and Ty Lawson added 10 in his first home game in a month to help the Tar Heels beat Florida State 90-77 on Tuesday night, keeping them in position to play for the Atlantic Coast Conference regular-season title this weekend at No. 6 Duke.

Marcus Ginyard added 13 points for North Carolina (28-2, 13-2), which led by 12 at halftime and maintained a comfortable margin through most of the second half for its seventh straight victory. The Tar Heels have won eight straight meetings and 19 of 22 in the series, and now can turn their attention to traveling to Cameron Indoor Stadium to face the Blue Devils on Saturday.

North Carolina, which shot 70 percent in the second half, spent 11 weeks atop the national rankings before losing 82-80 to Maryland here in January. The Tar Heels returned to No. 1 on Monday following Tennessee's loss at Vanderbilt last week.

Jason Rich had 27 points for the Seminoles (17-13, 6-9), who trailed by six points midway through the second half.

Florida State was trying to win four straight ACC games for the first time since the Sam Cassell-led Seminoles did it 15 years ago.

Lawson's health was a key concern for the second straight meeting of these teams. In the first matchup last month, Lawson sprained his left ankle in the early minutes of an 84-73 overtime win and missed the next six games. He returned to the lineup over the weekend, scoring four points in 21 minutes at Boston College.

On Tuesday, playing his first home game since Jan. 31, Lawson offered North Carolina fans a bit of a scare when he grimaced on his way to the bench with a hip pointer with 1:53 left in the first half.

He left for the locker room sporting an ice bag, and didn't return to the bench until 4 minutes into the second half. Still, he appeared to grow more comfortable as the game wore on, particularly in one stretch after the Seminoles had closed within 59-53 with 11:20 left.

The sophomore point guard knocked down an open jumper from the left side followed by a pull-up jumper in transition on the next play to spark an 8-0 spurt, giving the Tar Heels a double-figure lead they would not relinquish.

But it wasn't easy. North Carolina had trouble getting open looks for Hansbrough inside — he didn't score his first second-half basket until the 7:40 mark — while second-leading scorer Wayne Ellington had six points on 2-for-9 shooting.