A season-high 1,803 fans filled McKale Center on Saturday evening.
Paige Whipple posted 15 kills on .343 hitting in the loss.
Arizona welcomes a pair of top-20 teams to McKale this week.
Julia Patterson had 46 assists, 13 digs and 10 kills in the loss to No. 17 Utah.
Down 0-2, Arizona rallied back to force a fifth set, but fell in five at Colorado.
Arizona volleyball will face Colorado and Utah on the road to begin November.