DENVER -- Transfer Dee Hart rushed for 139 yards and two touchdowns in his Colorado State debut to help the Rams rally for a 31-17 win over Colorado on Friday night.

Colorado State's Treyous Jarrells finished with 121 yards, giving the Rams two 100-yard running backs in a game for the first time since 1996.

After Colorado State trailed most of the game, Garrett Grayson put the Rams on top for good with a 16-yard TD pass to Rashard Higgins early in the fourth quarter. Hart extended the lead minutes later with a 3-yard rush as the Rams beat the Buffs for a second time in three seasons.

Sefo Liufau threw for 241 yards and a pair of touchdowns to Nelson Spruce for Colorado.

Hart spent three seasons at Alabama, where he appeared in 17 games and carried the ball 43 times for 172 yards. He joined the Rams this fall as a graduate student and instantly vaulted to the top of the depth chart.

Most of the week, Colorado State coach Jim McElwain played up the underdog angle, saying the Buffs were a Pac-12 team with more resources and more talent. But the Rams were the ones coming off a bowl win last season.

They struggled early on offense under the senior leadership of Grayson, who's coming off a season in which he threw for a school-record 3,696 yards. With the passing attack stymied, Colorado State simply turned to its running game as Hart and Jarrells battered and bounced off Buffalo defenders.

Hart's familiar with McElwain, dating back to when the coach served as the offensive coordinator of the Crimson Tide from 2008-11.

Hart & Co. are trying to replace Kapri Bibbs, who rushed for 1,741 yards and 31 TDs last season.

Early in the second half, all the momentum appeared to be with Colorado when Grayson fumbled and Liufau capitalized by throwing his second TD pass of the night to Spruce, who made a one-handed catch.

Soon after, Jarrells made it 17-14 with 6:18 left in the third on a 3-yard run.

Spruce is taking the place of electric receiver Paul Richardson, who was drafted by Seattle. Spruce may not have Richardson's blazing speed, but has the ability to find space and catch about anything thrown to him. That's why Liufau called Spruce his "safety blanket."

It's not like Spruce doesn't have speed, though, as he showed when he deked Colorado State cornerback DeAndre Elliott at the line of scrimmage and hauled in a 54-yard TD pass in the first quarter.

That long play caught the attention of Richardson. He wrote on his Twitter account shortly after the play "that young man is a baller."

Former Olympic swimmer and Colorado State alum Amy Van Dyken-Rouen -- along with her husband, former Colorado punter Tom Rouen -- took part in the opening coin flip. Van Dyken was recently released from a Denver-area hospital to continue her rehabilitation after an all-terrain vehicle crash left her paralyzed just below the waist.