Hogg’s head appeared to make contact with the left arm of Le Roux when tempers flared in the second half of a fractious second match at Cape Town Stadium.
Footage and stills of the incident have been circulated on social media, but the Scotland captain rejects claims that he bit the South African
In a statement released by the British and Irish Lions, Hogg said: "Following speculation that has surfaced online, I would like to categorically deny any foul play in last night’s game. I would never bite an opponent and I am annoyed and upset by this unsubstantiated accusation. I’ve always been proud of playing rugby in the spirit of the game.
"Respect to the Springboks for their deserved win yesterday. The squad is hurting after last night’s defeat, but it’s all to play for next week. It’s going to be a cup final and everyone’s going to be up for it."
The Springboks won 27-9 during a match which got overheated at times. Wingers on each side were yellow-carded and Duhan van der Merwe and Cheslin Kolbe were both lucky to avoid red.