Butler extended the nation's longest winning streak to 21 games after dominating UTEP in the second half to take the first-round win.
No. 5-seeded Butler came back from a six-point halftime deficit, with Mack scoring 18 after the break. He went 7 of 9 from beyond the arc and also had four assists and four rebounds.
"We came out with some nerves, but in the second half, we came out firing," Hayward said.
UTEP ended the season with 26 wins, but two straight losses after going down today and to Houston in the Conference USA championship game.
"I'm frustrated because we're a lot better than we showed today," Caracter said.
The Miners shot only 37. 5 percent from the field in the second half.
"It started with our defense," Mack said.
Butler moves on to play No. 13-seeded Murray State in the second round.