By Dan Marsh The Manchester derby is always a tense affair – both on and off the pitch. Manchester United travel to Manchester City on Sunday hoping to avenge the 3-0 defeat that was inflicted upon them by the reigning Premier League champions back in October. Erling Haaland scored twice back then with Phil Foden grabbing the other goal on a chastening afternoon for Erik ten Hag. Understandably given the rivalry between the two teams, previous affairs have provided plenty of fireworks. And on one occasion back in 2017, the drama spilled over past the final whistle. Manchester City may have lef…