Jay Ajayi amasses 280 yards and 3 touchdowns to lead Boise State past Colorado State 37-24

Boise State running back Jay Ajayi (27) leaps into the end zone for a touchdown during the first half of an NCAA college football game against Colorado State in Boise, Idaho, on Saturday, Sept. 6, 2014. (AP Photo/Otto Kitsinger) (The Associated Press)

Boise State running back Jack Fields (21) fends off Colorado State defensive back Bernard Blake (23) during the first half of an NCAA college football game in Boise, Idaho, on Saturday, Sept. 6, 2014. (AP Photo/Otto Kitsinger) (The Associated Press)

Jay Ajayi scored three touchdowns and amassed 280 yards of total offense Saturday night to lead Boise State past Colorado State 37-24 in the Mountain West Conference opener for both teams.

Boise State coach Bryan Harsin notched his first career head-coaching victory to move to 1-1 and avoid the Broncos' first 0-2 start since 2005.

Colorado State (1-1), which rushed for 266 yards in its season-opening win over in-state rivals Colorado, gained 28 yards rushing on 23 carries. The Rams were forced to rely on Garrett Grayson, who was 31-of-58 passing for 434 yards with three touchdowns and two interceptions.

Ajayi ran for 219 yards on 33 carries and caught four passes for 61 yards. He scored on runs of 8 and 14 yards and caught a 21-yard touchdown pass to help Boise State build a 30-10 halftime lead.