AIR FORCE ACADEMY, Colo. (AP) Just as Brett Rypien released his fourth touchdown pass of the night late in the second quarter, the Boise State quarterback took a shot to the chin from a defender, opening a cut that required stitches to close.

Sewn up at halftime, Rypien didn't miss a beat, finishing with five touchdown passes - three to John Hightower - and Boise State pulled away in the late going to beat Air Force 48-38 on Saturday night.

''I don't like the getting hit part, and I think that comes a little bit with the situation,'' said Boise State coach Bryan Harsin. ''He got his chin taken care of. That's not what you want from your quarterback but at the same time he's standing in there and delivering the ball. The number one requirement for a quarterback is toughness, and he's been displaying it all year long.''

Rypien completed 20 of 34 passes for 399 yards with touchdowns of 61, 44 and 18 yards to Hightower, 21 yards to A.J. Richardson and 35 yards to C.T. Thomas. It was his fifth 300-yard passing game of the season and 20th of his career, most in school history.

Rypien didn't have much of a chance to see Thomas' catch because of the immediate hit he took after releasing the throw.

''That last play we scored (at the end of the half) I got one under the chin, but we scored so it made it feel a little bit better,'' Rypien said.

And the one after that, too.

''We'd never won here'' at Air Force, Rypien said. ''It was something that was a huge motivating factor for us. It means a lot.''

Hightower finished with eight catches for 182 yards and Sean Modster had six receptions for 101 yards for Boise State (6-2, 4-1 Mountain West), which won for the first time in three trips to Air Force (3-5, 1-4). Boise State's Alexander Mattison ran 22 times for 136 yards and a touchdown.

Isaiah Sanders was 10 of 15 for 210 yards and two touchdowns. He also ran for 97 yards and another score for the Falcons.

Haden Hoggarth's second field goal, a 47-yarder with 12:14 remaining, restored a 10-point lead for the Broncos. But Air Force again came back, driving nearly the length of the field before Sanders shoveled a 5-yard pass to Kadin Remsberg for a touchdown, pulling the Falcons to within three points with 5:24 remaining.

It didn't take long for Boise State to answer. Hightower shot past cornerback Zane Lewis' press coverage near the line of scrimmage and sprinted into the clear along the right sideline. Rypien spotted him, threw downfield and Hightower caught it on the run to complete the 61-yard score with 3:21 left.

''It came down to the O-line blocking and Brett making a wonderful pass and me trying to do what I can,'' Hightower said.

Air Force failed to convert a fourth down near midfield and Boise State ran out the clock to secure the victory.

Falcons coach Troy Calhoun said his squad went toe-to-toe offensively with the Broncos in the first half but couldn't sustain the pace.

''We've got to convert; we've got to have a little more manageable third downs, especially in the second half,'' Calhoun said.

The Broncos took a 38-31 lead into the fourth quarter, getting a 30-yard field goal from Hoggarth and a 1-yard touchdown run by Mattison that was set up by Avery Williams' 67-yard punt return to the Falcons' 5-yard line. Air Force squeezed in a 30-yard field goal by Jake Koehnke.

Rypien threw his fourth touchdown pass of the game to Thomas with five seconds left in the second quarter, allowing the Broncos to pull into a 28-all tie in a wild first half that saw the teams taking turns zipping down the field.

The Broncos broke on top with two quick first-quarter scoring strikes from Rypien to Hightower around Air Force's first touchdown, a 17-yard burst up the middle by fullback Cole Fagan.

The teams traded scores to start the second quarter with Sanders and Marcus Bennett teaming up for a 20-yard touchdown pass and Rypien connecting with Richardson.

The Falcons finished off a 21-point second quarter with Sanders' 5-yard touchdown run and halfback Joseph Saucier's 32-yard touchdown pass to wide receiver Andrew Smith that pushed Air Force briefly in front 28-21.

THE TAKEAWAY

Boise State: With the victory, Boise State became bowl eligible. Rypien matched his career high with five touchdown passes and the Broncos fleet wide receivers were able beat the Falcons secondary at key moments to come out on top in a shootout for a third consecutive win.

Air Force: The Falcons were denied in a bid for their first back to back wins of the season. They managed to trade blows offensively with the high-powered Broncos but in the end just couldn't contain Boise State's passing game.

UP NEXT

Boise State: Returns home to host Brigham Young on Saturday night.

Air Force: Plays at Army on Saturday with the Commander-in-Chief's Trophy on the line.

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