"It's uncalled for - no need for players to take that kind of abuse," Nel told Cricinfo during Essex's Championship match against Northants at Chelmsford. But he shrugged the incident off, saying: "I can take it because it can happen everywhere but there's no reason to get abuse from someone who doesn't even know what the word properly means. Racism doesn't deserve a place in any sport."
Russell Chapman, a spectator near the scene, stood up and told the man he could not engage in racist language. "I shouted at the guy 'You can't say that - why are you using that sort of language?'" he told Cricinfo. Nel then asked the unnamed spectator to be quiet. The scenes were captured on Sky Sports.
Ronnie Irani, Essex's captain said, "I shook Russell's hand after the game and said thanks very much to him because there are not a lot of people in this world who do step up and say 'Hold on a minute, that's rude'."
Essex's Healthy and Safety Officer will be filing a report to his opposite number at Surrey as he was close to the incident on the day and involved in ejecting the spectator.
It's not the first time Nel has been a victim of racism. Last year, on tour with South Africa in Australia, the board lodged an official complaint after spectators shouted insults at him and other members of the squad.
Jenny Thompson is assistant editor of Cricinfo