Samir Nasri and Emmanuel Frimpong clashed in the tunnel after Sergio Agüero's 83rd-minute goal allowed Manchester City to beat Arsenal 1-0 and advance to the semi-finals of the Carling Cup.
The former team-mates had tussled throughout the tie and at the end of the match they appeared to start arguing as the teams walked off the pitch, before their disagreement continued in the tunnel.
An Arsenal spokesperson confirmed the bust-up and said: "Words were exchanged - that was that, there were no punches thrown but there was a lot of noise. Sami was speaking in French and Mani wasn't. It was handbags but they didn't even touch."
Nasri had received boos throughout the game from the home support at the Emirates following the Frenchman's move to City from Arsenal in the summer. Following his departure from the north London club Jack Wilshere tweeted then: "Good luck to my friend @Nanas08 (mr Nasri) learnt a lot from him. World class player! Will be missed!" But Frimpong appeared to mock this or Nasri's decision when replying: "'Pfffff come on Jack."
While Arsène Wenger said he did not see the argument and admitted "frustration" at his side's defeat after they had dominated the tie, Roberto Mancini stated that only in January could he assess City's chances of winning all three domestic trophies this season. He said: "I don't know if we can win all three. The season is hard. December and January will be crucial months because we play big games every three days. After January we will know if we can win or not."
Regarding Nasri, who is yet to become a regular first-choice at City after his £25m move, Mancini added: "I think Nasri can play better than tonight. It [the booing] maybe affected him. It's not easy for him after being here for a few years. He's a very top player. When you arrive in a new team sometimes it takes to settle in. He can improve a lot because he is a champion."