But the businessman, Jared Mortimer, who runs a clothing company, told the Star newspaper that Pistorius was drunk, poked him in the chest and insulted his friends and South African President
Mortimer is friendly with several of Pistorius' former friends.
The incident at the VIP Room in Johannesburg occurred days after Pistorius’ defense lawyers closed their case in Pretoria’s high court, where he is on trial for murder in the shooting death last year of his girlfriend,
A grainy photograph emerged on Twitter showing a blurred figure that appeared to be Pistorius at the nightclub.
The VIP Room has a private section. Burgess said Pistorius was sitting in a quiet area of the section with his cousin when Mortimer approached.
"The individual in question, according to our client, started to aggressively engage him on matters relating to the trial," she said. "An argument ensued during which our client asked to be left alone. Oscar left soon thereafter with his cousin."
"Oscar said to me, 'Oh, you are the notorious Jared Mortimer,' " Mortimer told the Star. He said Pistorius told him that some of Mortimer's friends had treated him badly.
"Then he started talking about some of my friends, and he said he had statements and evidence that would get my friends into trouble. But he wouldn't use it because he wasn't that kind of person.
He claimed that the double-amputee athlete jabbed a finger aggressively in his chest, so Mortimer pushed him, and Pistorius fell backwards over a chair.
"He was poking me and saying that I would never get the better of him. He was close to my face and at that point I pushed him to get him away from me. A chair was behind his legs and he fell to the ground," Mortimer told the Star.
"I said to my friend, 'Check over there, there's a fight,'" one witness who did not want to be identified told the Star. He said he saw people holding two men apart from each other. The second man then left the club.