LAS VEGAS -- Ryan Harrison made a 19-yard field goal with 2:36 to play to give Air Force a 29-28 victory over UNLV on Saturday night.
Tim Jefferson threw two touchdown passes to help the Falcons (5-2, 3-1 Mountain West) improve to 4-0 on the road this season.
Down 28-20 after UNLV's Frank Summers' 45-yard TD run on the first play of the fourth quarter, the Falcons cut it to 28-26 on Jefferson's 44-yard touchdown pass to Kyle Halderman with 13:47 to go. Halderman was stopped on a 2-point conversion attempt.
Jefferson, a freshman, led the Falcons on a 91-yard drive to set up Harrison's winner, his third field goal of the game. The freshman quarterback ran for 105 yards on 13 carries and completed six of seven passes for 167 yards.
"He stepped up and made some big plays," Air Force receiver Ty Paffett said. "He's going to be fun to watch the next three years."
Jefferson split time with senior Shea Smith last week in a 35-10 victory over San Diego State, then played the entire game against UNLV.
"You can see the maturation process that is taking place," coach Troy Calhoun said. "He made some big plays, but we aren't a single guy team. We're a full unit."
UNLV's final possession stalled at the Air Force 47 with 57 seconds left.
Air Force fullback Todd Newell opened the scoring with a 52-yard run with 5:48 to play in the first quarter, and the Falcons made it 14-0 in the second quarter on Jefferson's 28-yard pass to Josh Cousins.
UNLV (3-4, 0-3) cut it to 17-14 by halftime when Omar Clayton threw a 28-yard touchdown pass to freshman Phillip Payne. The score was Payne's seventh touchdown this season, which leads all freshman receivers. C.J. Cox scored UNLV's first points on a 5-yard run at the 8:14 mark of the second quarter.
UNLV took its first lead in the third quarter when Clayton threw a 9-yard touchdown pass to Casey Flair for a 21-20 advantage with 3:09 to play in the quarter.