Barrett ran back an interception and Bell brought back a fumble for a score, two of the four mistakes forced by Colorado State (3-7, 2-4 Mountain West). Donnell Alexander ran for a career-high 139 yards, his second straight 100-yard game, and two touchdowns.
The Rams had lost seven of eight.
Tim Cornett ran for 102 yards on 20 carries for UNLV (2-9, 2-4). Cornett became the first Rebel to have eight 100-yard games in a season since Icky Woods did it in 1987. Nick Sherry was 12 of 30 passing for 139 yards, a touchdown and two interceptions.
The Rebels haven't won at Hughes Stadium since Nov. 20, 2002, and extended their road losing streak to 21 games. They failed to win back-to-back games for the first time since 2008.
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Running back Devontae Booker had 124 combined yards and a touchdown, and Utah spoiled Jim Harbaugh's Michigan coaching debut, beating the Wolverines 24-17 on Thursday night.
Arizona star linebacker Scooby Wright will have an MRI after injuring his left knee in the first quarter of the Wildcats' season-opening 42-32 win over UTSA on Thursday night.
Trevone Boykin threw for 246 yards and a touchdown and ran for 92 yards and another score to help No. 2 TCU outlast Minnesota 23-17 on Thursday night.
All-American defensive end Shawn Oakman and safety Orion Stewart have been suspended for Baylor's season opener Friday against SMU for a violation of team rules, a school spokesman told ESPN.com.
Ohio State quarterback Cardale Jones is "doing fine" after he was released from the hospital Wednesday night after being treated for symptoms related to a migraine headache.
East Carolina receiver Trevon Brown will miss three games after being placed on probation for a violation of the school's student code of conduct.