A 3-1 loss at West Ham on Saturday lunchtime means the Red Devils have now not won in three matches, which has firmly piled on the pressure on Mourinho.
The visit of Valencia to Old Trafford is hardly likely to be a prospect either manager or players will relish, considering United have beaten Los Che just twice in eight meetings between the sides.
A fourth consecutive match without a win, which would also make it just three victories in their last nine, would surely spell the end of Mourinho’s tenure in Manchester.
Whilst a win would certainly have all associated with United breathing a sigh of relief, the Red Devils have a tough run of fixtures coming and the 4/5 (1.80) from 888Sport may prove a popular bet.
Perhaps not under as much scrutiny as he would have thought due to so much focus being on United, Neil Warnock is 5/1 (6.0) to be the next Premier League manager to lose his job.
The Cardiff City boss has overseen four straight defeats, albeit against clubs who finished in the top seven last term, leaving the Bluebirds 19th on goal difference and with just two points.