After pressing the green flag, the "game" will automatically play and the ball and both helmets will move in random direction. If they intersect in just the right way, the respective team will score. If BYU scores, there is cheering; if Utah scores, there is booing. The ref pronounces the winner when the game clock counts down to zero.
The script for the game clock resides on the background. The football sprite handles most of the code, detecting when it is touching either helmet. The cheerleader switches based on who scores and when the broadcast event "game over" is sent - the ref appears on the field to announce the winner. I did get some helpful ideas from the search on the Scratch site about how to go about establishing a timer.