After Nevada (2-3, 0-1 Mountain West) scored 10 unanswered points and pulled within a field goal at 13-10 in the fourth quarter, Ryan McAleenan intercepted a Tyler Stewart pass and ran 52 yards for a UNLV touchdown.
The play proved critical for the Rebels after their offense struggled in the second half after starting quarterback Blake Decker left the game in the final minute of the first half with an injury.
On his second play following Decker's injury, backup Kurt Palandech connected on a 25-yard pass to receiver Kendal Keys. On the next play from the Nevada 12-yard line, Palandech scampered into the end zone for the Rebels second score of the game with :30 left in the half, sending UNLV (2-3, 1-0) into halftime with a 13-0 lead after outgaining the Wolf Pack 246-103.
Stewart completed 20 of 44 passes for 202 yards and a touchdown and added 61 yards rushing on 11 carries.
UNLV's Keith Whitley rushed for 80 yards on 16 carries.
Nevada's offense regularly started deep in its own territory, with an average start at its own 11-yard line in the first half, thanks to solid punting from Logan Yunker, a Nevada transfer.
On three consecutive possessions in the first half, Yunker pinned the Wolf Pack inside its own 10-yard line and did it a fourth time in the second half (2, 3, 7 and 8, respectively).
Attendance was 29,551, the ninth largest in Mackay Stadium history.