Also, Colorado's Billingsley out for season
Cox will replace junior starter Joel Klatt, who suffered a neck sprain just before halftime of CU's 42-14 loss to Oklahoma State last weekend.
Klatt had been listed as day-to-day, but Barnett said Tuesday that Cox would start regardless of Klatt's physical status.
Cox has played in three games this season, completing 17 of 23 passes for 187 yards and one touchdown.
On Tuesday, Billingsley had arthroscopic surgery on his left knee that revealed damage that had occurred since an initial procedure in August. The junior, who has been bothered by excessive swelling, will be on crutches four to six weeks, but Barnett hopes he will be ready for spring practice.
Both players will apply for medical redshirts. Billingsley played in two games this season, Hollis in one.
Copyright 2004 by The Associated Press
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