It comes after a spike in positive COVID-19 cases that also left Arizona State unable to play against California this weekend.
"As we announced Friday for our contest against Cal, the number of positive cases in the last few days has put our team below the Pac-12's minimum threshold of 53 available scholarship student-athletes under the league's game cancellation policy," ASU athletic director Ray Anderson said in a statement. "Unfortunately we are in the same situation for this week's scheduled game with CU.
"We have consulted with the Conference and Colorado officials and have decided to make this prompt announcement so alternative scheduling options can be considered in the overall interests of the Conference and our peer student-athletes and coaches."
After ASU and Utah both could not play this week, the conference arranged a Sunday morning game between Cal and UCLA. Colorado is allowing for the possibility it could still play this week.
"We will look at any and all options about us being able to play this weekend," CU athletic director Rick George said in a statement. "It's too early right now to gauge everything, the conference did pair UCLA and Cal today on very short notice, so we'll have to see what transpires day-to-day around the league."
The game between ASU and Colorado will be ruled a no contest, per league policy.