Umpiring a Gael Monfils match demands sound vision and fast hands.
While chair umpire John Blum made the right calls, he couldn't quite make the catch on a Monfils return.
Video: Match-Fixing Bombshell
Watch what happens when Monfils is a little late trying to return a rocket serve from Milos Raonic during the Canadian's Australian Open quarterfinal.
Though the chair umpire dropped the ball, this fan did not stretching for a fine snatch off a Milos miss-hit.
Photo credit: Tennis Australia