PARADISE ISLAND, Bahamas — After yet another second-half possession ended with a miscue, all Roy Williams could do on the North Carolina sideline was cross his arms and shake his head.
It was that sort of day for the Tar Heels.
Alex Barlow and Kelan Martin each scored 17 points, and cold-shooting Butler grabbed 29 offensive rebounds on the way to upsetting No. 5 North Carolina 74-66 on Wednesday in the opening game of the Battle 4 Atlantis.
"The game of basketball is pretty simple," Williams said. "Just put the ball in the hole."
And Carolina simply didn't do enough of that until it was too late.
Marcus Paige shook off a slow start and scored 18 points for North Carolina (3-1). Brice Johnson added 11 for the Tar Heels, who missed 12 of 13 shots from the floor in one second-half stretch and misfired on 14 of their 32 tries from the foul line.
"They outplayed us and definitely outcoached us," Williams said. "And we had some chances at the end ... but again, you have to congratulate their defense for doing such a good job."
Butler's shooting numbers were even worse, and it didn't matter. The Bulldogs shot 31 percent, including a staggering 7 percent in the final 8 minutes, missing open shots from near and far all afternoon.
"I know our guys would have loved to make shots," Butler coach Chris Holtmann said.
Kameron Woods had 13 rebounds and Roosevelt Jones scored 12 points for the Bulldogs (4-0), who topped the Tar Heels for the second straight time. Butler beat North Carolina at the Maui Invitational in 2012.
A 16-4 run over a 5½-minute second-half stretch was key for Butler, turning a 43-41 lead into a 59-45 cushion.
When opponents shot 22 for 72 or worse in the Williams era, the Tar Heels were 21-0 — until Wednesday.
"They got 15 more shots than us and we both turned the ball over 19 times," Paige said. "A coach Williams team, if you look at the backboards they usually tell the story, and we got dominated."
Paige was ice-cold early on a steamy day on the island, missing nine of his first 10 shots. But a pair of 3-pointers followed by a three-point play in a late 3-minute span pulled North Carolina within 69-66.
The Heels got no closer.
Barlow made two quick 3-pointers after halftime, putting North Carolina in a second-half hole for the first time this season.
"We knew we needed to come out in the second half and try to get on them early," Barlow said.
North Carolina: F Kennedy Meeks blocked a career-high five shots. ... The Tar Heels had first-half scoring runs of 11-0, 12-0 and 11-0 in their first three games, but managed only one stretch of five straight points in the first half Wednesday.
Butler: The Bulldogs had lost their last seven games against Top 25 teams. ... Four of Butler's starters Wednesday played when the Bulldogs beat North Carolina in Hawaii two years ago. ... Starting guards had averaged 8.0 points against the Tar Heels in the season's first three games. Barlow had 11 by halftime.
SURVIVE THE COLD
Each of Butler's starters came into Wednesday shooting at least 50 percent this season. None got there Wednesday, and the Bulldogs' first string shot a combined 16 for 57.
Williams pointed out postgame how his Kansas team lost to Ball State in the opening game of the Maui Invitational to start the 2001-02 season and wound up in the Final Four. "There's a lot more important things going on," Williams said.
North Carolina: Faces No. 22 UCLA in Thursday's consolation round.
Butler: Faces Oklahoma in Thursday's semifinals.