Virginia guard Kyle Guy had 17 points to lead the Cavaliers to a 53-43 win over North Carolina. (Chet Strange/Getty Images)

London Perrantes went to his barber shop after Virginia suffered its fourth consecutive loss against Miami last week, a desperate man in search of a clean shave and a new start.

The Cavaliers beat North Carolina State after that, and Perrantes vowed a new beginning for his previously struggling Virginia teammates — a bold statement, considering that up next was No. 5 North Carolina, the team that handed the Cavaliers their worst loss since 2013 just nine days before Monday night’s rematch.

But Virginia made good on Perrantes’s promise, defeating the Tar Heels, 53-43, in Charlottesville as fans at John Paul Jones Arena jumped so hard they shook the metal barriers separating the crowd from reporters. The Cavaliers played like a different team than the one that lost at North Carolina by 24 points, having patched up every flaw Virginia Coach Tony Bennett pointed out after that game.

“We just weren’t tough enough defensively down there,” Bennett said. “. . . When you make shots, that makes the biggest difference. But I thought we had more purpose in our cuts, in our screens. . . . We played the right way. We knew the formula, we knew how we had to play — didn’t know if it would get us a win — but we knew what was the way we had to do it. For the most part we stayed true.”

No. 23 Virginia (20-9, 10-7 ACC) shined on defense all night, holding a North Carolina team that entered Monday averaging 86.4 points per game to its fewest points since a 47-40 loss at Duke in 1979.

In the second half, the Tar Heels shot just 27.6 percent (8 for 29) from the field and made just 1 of 11 three-point attempts. They ended the night with 14 turnovers (Virginia had just four) to give away 18 points and, despite their length, had just 10 offensive rebounds to Virginia’s 13. Perrantes held reigning ACC player of the week Justin Jackson to just seven points on 3-for-10 shooting. The forward had scored at least 20 points in each of his previous four games, including against the Cavaliers the first time around.

“The most aggressive team won tonight,” North Carolina Coach Roy Williams said. “. . . Tonight I don’t think it’s as much what we did wrong as it was how good their defense was.”

Virginia’s defense facilitated good offense, as well. The Cavaliers shot 10 for 24 from beyond the arc and were led by Kyle Guy’s 17 points, including 5-for-7 shooting from three-point range. The freshman from Indiana was downright giddy for much of the second half, feeding off what Bennett called one of the better crowds he’s ever had in Charlottesville. Guy threw his hands up in exaltation and tipped his head back to laugh when center Jack Salt tipped in a layup with 6:25 to play before the Cavaliers forced a defensive stop on the other end to maintain a nine-point lead.

Perrantes added 13 points, including three three-pointers, and junior guard Devon Hall had 11.

Point guard Joel Berry II led North Carolina (25-6, 13-4) with 12 points as the only Tar Heel in double figures.

The Cavaliers had thought of Monday’s game as a “golden opportunity” before they even arrived to warm up. The Tar Heels came to Charlottesville with the No. 1 seed and a double-bye in the ACC tournament, which starts March 7 in Brooklyn, already secured. Virginia had memories of a sobering loss to assuage, and they played like their pride was on the line.

“We had nothing to lose,” Perrantes said. “We had two more [regular season] games left, North Carolina was looked at as one of the best teams playing these past couple weeks, and we had nothing to lose.”

“I think that when we were at Chapel Hill, we were a completely different team,” Hall added. “We didn’t take it personally on the defensive end, and they were just getting anything they wanted — dunks, wide-open jumpers.”

This time around, Perrantes got to pick his moments. North Carolina was chipping away at Virginia’s edge and was trailing 40-39 past the midpoint of the second half when the senior point guard pulled up and cranked out two three-pointers in a row to widen Virginia’s lead. The Cavaliers completed an 8-0 run and led by at least seven for the remaining seven minutes of play.

“I really enjoy watching [Perrantes] play when he’s playing someone else,” Williams quipped.

Virginia had leaned on Guy for an offensive spark in the first half. After the Cavaliers started the night shooting 1 of 6 from the field, the guard made three three-pointers before intermission to help Virginia to a 27-23 halftime lead.

Guy agreed that Monday was a coming-out party for the new and improved Virginia, which plays its regular season finale Saturday against Pittsburgh — another team the Cavaliers lost to earlier this season.

“It was probably the best thing that happened to us, to get slapped in the face like that at Chapel Hill,” Guy said. “We wanted to make a statement coming back home.”