JACKSONVILLE, Fla. -- North Carolina coach Roy Williams declined to disclose how he celebrated in the locker room after getting back to the Sweet 16. The smile on his players' faces made it clear it was something they had never seen.Marcus Paige scored 22 points, including 20 in the second half, and the fourth-seeded Tar Heels North beat No. 5 seed Arkansas 87-78 in the NCAA Tournament on Saturday to advance to the round of 16 for the first time in three years.Things apparently got crazy in the locker room afterward."It would be the most embarrassing thing of my life probably, so I'll just leave it like that," Williams said. "But I do enjoy acting silly and having fun. I am emotional and wear my feelings on my sleeve a lot in both directions, very happily or very mad, too. ... I hope the cameras weren't all over the locker room, let's put it that way."This much we know: The game highlights will feature Paige.The junior guard missed seven of eight shots in the first half, including all three from 3-point range, and was pretty much a non-factor as the Tar Heels let the Razorbacks keep things close.But he took over in the second half, scoring 13 of his team's 17 points during a 5-minute stretch that helped North Carolina (26-11) build a double-digit lead. The Tar Heels held on from there, thanks partly to Paige closing things out from the free-throw line and with his ball-handling skills."Well, if I could play just as well in the first half as I do in the second half, I would prefer to do that, but sometimes it happens that way," said Paige, who has been nicknamed "Second Half Paige." "Sometimes, if you have a poor first half, you want to do whatever you can to erase that and make up for it the second, and that's what I've been able to do a couple times."UNC advanced to play either No. 1 seed Wisconsin or eighth-seeded Oregon in the West Regional next week in Los Angeles. It will be Carolina's 26th appearance in the Sweet 16.Michael Qualls led Arkansas (27-9) with 27 points and 10 rebounds. Southeastern Conference player of the year Bobby Portis finished with 18 points and 14 boards.The Razorbacks played to their strength in a fast-paced first half that included a combined 79 shots, but things slowed down considerably after the break -- and that favored Carolina."I thought the thing that really disrupted the game was a lot of free throws, a lot of whistles," Arkansas coach Mike Anderson said. "It was almost opposite of the first half. The first half they let them play, and I guess in the second half they said, Let's slow this down. We can't keep up with them. Let's slow it down."The victory was no given for UNC, especially after it eked out a victory against Harvard in their opener. The Tar Heels turned the ball over 17 times against the Crimson and knew that kind of performance against the pressing, trapping Razorbacks could mean a third consecutive early exit from the tournament.The Tar Heels responded with a relatively clean game. They turned it over just six times in the first half and 16 total. They broke the press early, getting easy shots in transition and at the rim.The only thing that slowed down UNC was foul trouble.Kennedy Meeks picked up his fourth foul early in the second half, limiting Carolina's inside game. Meeks returned later and sprained his left knee. He will be re-evaluated when the team gets back to Chapel Hill.Carolina went small without Meeks, and turned to Paige.After Arkansas took a 59-58 lead on Jabril Durham's 3-pointer from the corner, Paige drove by three defenders and got fouled as he made a circus shot. He capped the three-point play and then added consecutive treys a few minutes later that proved to be daggers."Marcus was sensational in the second half," Williams said.---MORE HELPFreshman Justin Jackson, who hit the game-winning shot against Harvard, came up big again down the stretch. Jackson scored six consecutive points -- he made two layups and hit two free throws -- that prevented the Hogs from making a comeback. Jackson finished with 16 points. "I was just getting easy looks," he said. "It wasn't really much that I did. I was just trying to cut, get to the open spot and my teammates were finding me."CLEAN SHEETUNC point forward J.P. Tokota added 13 points, eight assists and no turnovers. He also had five rebounds and two steals.TIP-INSArkansas: Legendary Arkansas coach Nolan Richardson attended the game. ... The Razorbacks lost despite getting 20 offensive rebounds, nine steals, hitting eight treys and making 22 of 27 free throws. ... Portis had five of the nine steals.North Carolina: Coach Roy Williams improved to 32-8 in the NCAA Tournament with his alma mater, tying late and legendary coach Dean Smith for the program's most wins in the tourney. ... Williams also notched his 750th career win, becoming the 15th coach in Division I history to accomplish the feat.