SAN DIEGO -- Making his first start for the ground-oriented San Diego State, redshirt freshman quarterback Christian Chapman came through to help deliver the Aztecs their first outright conference championship in 29 seasons.
Chapman threw for 203 yards and one touchdown, and Donny Hageman kicked a 46-yard field goal with 5:10 to go to give the Aztecs a 27-24 victory against Air Force in the Mountain West Conference championship game Saturday night.
"It's surreal when you do something like this; you are happy," Chapman said. "I'm kind of waiting for it to sink in."
Coach Rocky Long said the Aztecs expected big things from Chapman, who's from Carlsbad in northern San Diego County, and they got it.
Chapman started in place of Maxwell Smith, who suffered a knee injury in the regular-season finale against Nevada.
He said he wasn't nervous coming in. He had a low-key Friday night, watching The Hunger Games and then falling asleep.
"I was all right," said Chapman, who completed nine of 14 passes.
"We thought he would play well, we were confident about that," Long said. "We had no idea that he would play as good as he did and thank goodness he did because we needed him to play for us to win. I thought he played great and it was unbelievable for a backup quarterback to come in and play like that. And he's young -- a redshirt freshman."
Said Air Force coach Troy Calhoun: "He is a good player and we knew that coming in. I thought he played well today, too."
SDSU could be headed for the Hawaii Bowl on Christmas Eve in Honolulu.
This is SDSU's first outright title since winning the Western Athletic Conference crown in 1986. They shared the 2012 MWC championship with Boise State and Fresno State.
Air Force (8-5) tied it on Timothy McVey's third touchdown, a 2-yard run on fourth down with 11:49 to go.
Chapman threw a 48-yard pass to Micah Holder to the Air Force 25 but a 6-yard loss and a holding penalty moved the ball back, forcing the Aztecs to settle for Hageman's go-ahead kick.
Air Force had two more possessions. It punted with 3:35 left and the game ended on Karson Roberts' desperation pass.
The Falcons could be heading for the Armed Forces Bowl in Fort Worth on Dec. 29.
Chapman threw a 24-yard touchdown pass to wide open D.J. Pumphrey, the league's Offensive Player of the Year, to tie the game at 7 on the first play of the second quarter.
The Aztecs made plenty of mistakes that cost them points.
Chapman threw a 28-yard touchdown pass to Mikah Holder on the Aztecs' second possession but it came back because of a chop block penalty and SDSU was forced to punt.
SDSU then forced the Falcons to punt, only to see Holder have the ball bounce off his chest. Air Force recovered at the 10 and McVey scored on an 8-yard run two plays later for a 7-0 lead.
Air Force went ahead 17-10 on a 3-yard run by McVey midway through the third quarter. It was set up on a crazy play, when Air Force's Jacobi Owens fumbled at the Falcons' 40 and the ball was knocked forward several yards. Two Aztecs had a chance to recover but Air Force's Garrett Griffin jumped on it at the SDSU 28. McVey scored six plays later.
SDSU then scored on consecutive drives. Gordon gained 23 yards on fourth-and-1 from the 29 and scored on a 1-yard run three plays later to tie it at 17.
Penny's 28-yard TD run came early in the fourth quarter and gave the Aztecs a 24-17 lead.
Owens ran 17 times for 156 yards. McVey had nine carries for 48 yards.
"Everyone was fired up but it just wasn't enough today," McVey said. "We just didn't run the ball like we wanted to."