Journalist Rob Beasley, who has closely followed now-United boss Mourinho's career, wrote in his book - 'Jose Mourinho: Up close and Personal' - which is being serialised by the Daily Mail of a comment made by Mourinho towards Wenger.
“When Mr Wenger criticises CFC and Man United over the deal with Mata...I will find him one day outside a football pitch and I will break his face," said Mourinho on that occasion.
Arsenal's next trip to Stamford Bridge in October 2014 saw the duo almost come to blows, with Beasley explaining what Mourinho said: “He (Wenger) was asking for a red card and pressing the ref in my (Mourinho's) technical area. I told him to go back to his area. He pushed me.
“I told him, 'Here you do that, you know I can't react, but I will meet you one day in the street'.
Beasley added: “Now I don't think Jose was ever serious about having fisticuffs with the Frenchman, he was just huffing and puffing and letting off steam.
“I gave him the benefit of the doubt on this occasion, even though an article for me with Jose saying, 'Let's sort this out in the street, Arsene' would have been huge.
“I told Jose this could be a good story to show he took no nonsense from Wenger but I added that I thought it was best to leave it."