Colorado guard Sabatino Chen—who came into tonight's game averaging just 4.1 points per game—hit a buzzer-beater in Tucson to down third-ranked Arizona, only to find referees waving it off after a video review that appeared to back up the original call on the court of a good shot.

The undefeated Wildcats came back from a huge first-half deficit to tie the Buffaloes at 80 only to watch a chance at overtime appear to slip from their fingers as Chen's improbable three-point shot found the bucket. Despite the video clearly showing the shot to have been released with 0.1 seconds remaining on the clock—and the behind-basket red light not yet lit—officials waved off the shot, sending the McKale Center into madness. (Arizona went on to prevail in overtime.) [ESPNU]

Update (12:22 a.m.): NBC Sports' Rob Dauster explains further with the actual NCAA rule:

In games with a 10th-of-a-second game clock display and where an official courtside monitor is used, the reading of zeros on the game clock is to be used to determine whether a try for goal occurred before or after the expiration of time in any period. When the game clock is not visible, the officials shall verify the original call with the use of the red/LED light(s). When the red/LED light(s) are not visible, the sounding of the game-clock horn shall be utilized. When definitive information is unattainable with the use of the monitor, the original call stands.

The call on the court was of a made three. (Watch the referee at the bottom of the screen.) There's no way a rational human being can conclude the video provides definitive proof the shot did not get off before time expired; that is, unless you're a Pac-12 referee.