BYU's dream start hit a speed bump on Saturday, as the Cougars were upset by unranked Boise State 26-17 for their first loss of the season.
The 10th-ranked Cougars dominated the stat sheet with a 413-312 advantage in total yards, but they committed four turnovers, including two in Boise State territory, that proved costly.
Broncos wide receiver Khalil Shakir caught five passes for 66 yards in the win. Their rushing attack racked up 140 yards and two touchdowns on 45 carries and allowed them to control the clock.
Saturday's win marks Boise State's first victory over a team ranked in the Associated Press Top 10 since the 2010 Fiesta Bowl against TCU.
BYU quarterback Jaren Hall did throw an interception on the team's final drive with under two minutes to play, but the first three turnovers came on poor execution.
Tyler Allgeier fumbled the ball away at BYU's 24-yard line midway through the second quarter with BYU leading 10-3.
Boise State needed just four plays to get into the end zone and tie the score. Cyrus Habibi-Likio capped off the drive with an 11-yard drive.
On the ensuing kickoff, Lopini Katoa lost possession of the ball and the Broncos recovered. The Broncos took a 17-10 lead five plays later on Andrew Van Buren's third-down score from one yard out.
Two field goals put Boise State up 23-10 midway through the third quarter. BYU seemed poised to at least get a field goal on its first possession of the second half, but Katoa fumbled again at the Broncos' 18-yard line.
Allgeier did get BYU within six points on a touchdown run with 7:27 remaining in the fourth quarter. Boise State's ensuing possession sealed the win thanks to Jonah Dalmas' 22-yard field goal.
Dalmas was put in position to even have a chance to kick the ball after Shakir caught a 35-yard pass with two defenders around him.
Boise State (3-3) has had an inconsistent start to the season. It did play Oklahoma State and Central Florida close, losing both games by a combined six points. Head coach Andy Avalos got his first marquee win in his sixth game leading the program.
BYU (5-1) fells from the ranks of the unbeaten, but there are still plenty of reasons to be optimistic about the program. It already has wins over Pac-12 teams Utah and Arizona State, the latter of which is currently ranked No. 22 in the AP Top 25.