Originally set for March 16, the clash could now take place at an absolutely crucial time for the title race.
The typical end of season Premier League fixture pile-up is set to impact the Manchester derby substantially, with the Premier League clash potentially having to be delayed for over a month.
Following both teams progression into the FA Cup quarter-finals, the March 16 date has had to be binned with the next date available being April 2 or 3. However, this is the midweek before the semi-finals of the cup, which is also the initial date for United's league match at Wolves.
With the Red Devils or their quarter-final opponents destined to be in action the weekend of April 6, that fixture will also need to be moved and is set to compete with the Manchester derby for the preceding midweek option.
To make matters more complicated, ESPN report that the advent of both Manchester clubs reaching the semi-finals could see the clubs prefer not to schedule such a key derby in the build-up to a huge occasion at Wembley.
The following midweeks, of April 9 or 10 and 16 or 17, hold the Champions League quarter-finals and Manchester City appear likely to reach that stage of the competition, with either that or a United comeback against Paris Saint-Germain ruling out those dates.
The Premier League season must be completed by May 12 and the earliest chance for the derby to be played could end up being just three weeks before that date, on April 23 or 24.
By that point, the derby would take place with just three games left in the regular season and the result would likely have even bigger implications to the races for the title and Champions League qualification.
And, of course, it would create a huge double game week for Fantasy football fans with Manchester United travelling to Everton the weekend beforehand, while City tackles the small matter of Spurs at home.
