Porto coach Vitor Pereira has claimed that there was no racist abuse aimed at Manchester City players during the two sides' Europa League clash last Thursday.
City lodged a complaint to UEFA following the game, alleging that Porto fans had directed monkey noises at Mario Balotelli and Yaya Toure.
UEFA have confirmed that they are investigating the claims, but Pereira believes that the complaints were based on 'a misunderstanding'.
"I did not hear any racist comment. So I cannot comment on what I did not hear, I have no idea," said Pereira.
"Our supporters many times say, 'Hulk, Hulk, Hulk', but they are referring to our forward of great quality, as a way of motivating him.
"I was focused only on the match, to see what was happening inside the four lines, and I did not notice any comment that could force the club to make any apologies."
City take a 2-1 advantage into the second leg at the Ethiad Stadium this Wednesday.