LOGAN, Utah (AP) Boise State pulled onto the Utah State campus ranked No. 5 in the country in turnover margin with 12 consecutive wins against the Aggies. Those accomplishments, and probably the No. 21 ranking in the AP poll, went out the window by halftime Friday night.

The Broncos turned the ball over seven times and trailed by 35 in the first 30 minutes of a 52-26 loss to unranked Utah State.

Boise State had outscored its opponents 204-24 in its previous four games.

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''You try to stop the bleeding as fast as possible,'' Boise State coach Bryan Harsin said. ''You've got to go make plays. You've got to hang onto the football.

''We needed guys to work together. We needed to push some field position in our favor. It just didn't go that way.''

The 21st-ranked Broncos hadn't lost to Utah State in 18 years, but that at streak was all but officially over after two quarters. Utah State upset their Mountain West Conference rival thanks to seven first-half turnovers, including a 90-yard interception return by Marwin Evans as time expired in the half. The Aggies scored 21 points in the final 85 seconds of the first half thanks to two fumbles and the interception.

The 52 points are the most Boise State has ever allowed as a ranked team.

''We did everything the same as we usually do,'' Boise State safety Darian Thompson said. ''The locker room was fired up before the game. But when it started, they just came out with more fire.''

The Aggies' defense ruled the day with a historic effort. The eight total turnovers were the most since forcing seven against Arkansas State in 2003 - and matched that in the first half.

Boise State receiver Thomas Sperbeck then fumbled the ball away on the second snap of the second half.

The Broncos served up four fumbles and three interceptions in the first half, including Evans' score at the end of the half.

Boise State had just 10 first downs in the first half and allowed 35 points off the turnovers. The offensive line was simply overwhelmed in the first 30 minutes and quarterback Brett Rypien was regularly under pressure.

Rypien, the nephew of former NFL quarterback Mark Rypien, threw for 299 yards with three interceptions. He entered the game with one interception in four games. Sperbeck had a game-high 156 yards receiving on six catches. Running back Kelsey Young ran for 60 yards and two touchdowns for the Broncos.

''I don't know if I've ever seen anything like it in the first half,'' said Utah State coach Matt Wells, who added it was ''maybe the greatest win in program history. ... It's huge. I make no bones about it. I've been saying it - out of respect - the road to the championship goes through Boise. Till someone knocks them off the throne, it's theirs.

''I told our guys on Sunday, this isn't the championship game, but it puts you in the driver's seat.''

Utah State (4-2, 3-0) holds onto a share of first place in the Mountain Division with the win. Boise State (5-2, 2-1) falls out of first with its first conference loss of the season. Air Force (3-2, 2-0) is at Colorado State (2-4, 0-2) on Saturday.

Utah State hasn't won a championship in any sport since joining the Mountain West in 2013. The Aggies lost 50-19 in this meeting last year.

''I wanted to beat Boise State so bad since last year,'' Utah State quarterback Kent Meyers said. ''We really wanted revenge.''

Utah State linebacker Kyler Fackrell finished with 11 tackles, 2.5 for loss. He also forced a fumble and recovered two. Fellow linebacker Nick Vigil had a game-high 14 tackles, nine in the first half, two sacks, a forced fumble and a fumble recovery.

''I thought the guys fought,'' Harsin said. ''We knew what circumstances we put ourselves in and we had to dig out of it.''