Sometimes they wait to use it when they have to, usually on 3rd down. Boise St. never got to a 3rd down that drive. If they use it on 1st down and they keep moving the ball and picking up first downs, you waste it.
1st-10, BoSt45 4:50 J. Avery rushed up the middle for 2 yard gain
2nd-8, BoSt47 4:05 J. Avery rushed up the middle for 13 yard gain
1st-10, SJSU40 3:35 I. Johnson rushed up the middle for 14 yard gain
1st-10, SJSU26 3:08 I. Johnson rushed to the right for 9 yard gain
2nd-1, SJSU17 2:25 J. Avery rushed to the left for 5 yard gain
1st-10, SJSU12 1:54 J. Avery rushed up the middle for 2 yard gain
2nd-8, SJSU10 1:11 I. Johnson rushed up the middle for 10 yard touchdown. K. Brotzman made PAT
If they were going to use it, they should have used after 1st down when Avery got 2 yards.