First there was ‘Pizza-gate’ when the Arsenal squad pelted Sir Alex Ferguson – now Old Trafford has been hit with another mystery, ‘Milk-gate’.

The Manchester United boss was reportedly hit with milk during a tunnel fracas following Manchester City’s 2-1 win over their arch-rivals.

And Bookmakers PaddyPower are taking bets on who was responsible with South American duo Fernandinho and Nicolas Otamendi heading the market.

Spokesman Paddy Power said: “Would you be surprised if it turned out that Jose had thrown milk over himself? From drama queen to dairy queen.

“Though I also think that Romelu Lukaku is decent value – but he was probably aiming at Pep, of course.”