BOULDER, Colo. - Notes and observations from warmups before the Arizona Wildcats’ game against Colorado at Folsom Field on Saturday afternoon (12:30 p.m. Tucson time, Pac-12 Networks):
* Starting middle linebacker Treshaun Hayward was not spotted during warmups. Hayward’s absence would thrust transfer Jerry Roberts into the starting lineup. Roberts has appeared in three games this season, totaling 14 snaps and one tackle. Hayward ranks second on the team with 34 tackles.
* Starting right guard Josh Donovan is not in uniform. Second-year freshman Josh Baker will take his place. Baker has one career start, in the opener vs. BYU. He has played 190 snaps this season.
* Jamarye Joiner worked as a receiver during warmups, but it wouldn’t be surprising to see him get some snaps at quarterback in certain situations. Gunner Cruz will make his third career start at QB.
* Cornerback Isaiah Rutherford is back after missing last week's game vs. UCLA because of strep throat.
* UA kicker Lucas Havrisik was making field goals in excess of 60 yards during warmups. The elevation in Boulder is 5,328 feet.