[7] The COVID-19 pandemic prompted teams to play many sporting events behind closed doors with no spectators to maintain player safety and reduce large gatherings that can spread Coronavirus disease 2019 (COVID-19).

[15] The crowd noise sometimes included audio associated with the sport or home team, such as specific chants, and in the case of football in South Africa, the sounds of vuvuzelas.

[19] For the 2020 US Open, IBM trained its Watson artificial intelligence system to cue crowd noise automatically, using footage from past editions of the tournament to determine appropriate reactions to in-game events.

[20][21] In some cases, artificial crowd noise was paired with the use of augmented reality to fill in empty stands with CGI "spectators" (as used during La Liga and trialled by U.S. broadcaster Fox Sports),[22][23] or the use of virtual audiences displayed on video boards within the venue.

[25][13] One football writer argued that artificial crowds were "disingenuous" and created a disconnect with accounts of games noting the lack of spectators, and felt that viewers were missing out on the ability to hear on-field communications between players, arguing that "if a game that generally produces one of the most fierce atmospheres in the world is being played in front of a silent backdrop, that's as much a part of the story as the result.