Must not call a South African a "box"

There is a rather odd controversy recorded here where one white South-African-born cricket player referred to another white South-African-born cricket player by the Afrikaans word for "box".  Australians would understand that slang and its offensiveness. 

The curious thing is that both players concerned  were in fact playing for England against a South African team.  The abused player was in fact the England captain, who seems to have been pretty upset. 

The abusive guy is most unlikely to be selected to play for England again but he is undoubtedly a bit of an egotist so he deserves that.  It is principally a matter of team loyalty and team cohesion (important matters in sport) rather than speech,  as far as I can see.