Adler was doing play-by-play commentary on ESPN for Williams' Jan. 18 match against Stefanie Voegele, saying Williams was playing more aggressively after Voegele missed serves. When Voegele faulted on a serve, Adler described Williams as moving in and charging with a "gorilla effect" or "guerrilla effect." Because the words gorilla and guerrilla are pronounced similarly, it's impossible to say for certain which word Adler spoke.