Nkosi 'out for a couple of weeks'
Nkosi will take no part in this weekend's Currie Cup Final against Western Province and he is also set to miss the Springboks' upcoming end-of-year tour which starts with a match against Ireland in Dublin on November 11.
Nkosi was part of Allister Coetzee's Bok squad for the final two weeks of this year's Rugby Championship, but he has yet to earn a Test cap in the green and gold.
"S'bu [Nkosi] dislocated his elbow. There is no fracture and he will be out for a couple of weeks," said Everitt.
Nkosi has been a key part of the Sharks Currie Cup campaign this season scoring a total of eight tries.
Saturday's Currie Cup Final will be the Sharks' first since 2013 when they beat Province 33-19 at Newlands in Cape Town.