Manchester United go up against West Brom aiming to keep their thin hopes of Premier League title glory alive.
The Red Devils know nothing but a win will do, though will come up against a Baggies side on a high after a 0-0 draw with Liverpool in midweek.
And ESPN say Mourinho is concerned about facing West Brom, as he fears Alan Pardew’s men will time-waste in order to kill the game.
West Brom were criticised after the game against Liverpool.
It is said Mourinho watched footage from the match in the week and the Manchester United manager was left concerned by what he saw.
ESPN claim he has urged his players to do their utmost to ensure Pardew’s team do not run down the clock.
And Mourinho was also surprised by the lack of stoppage time in the Liverpool game, thinking West Brom’s antics to warrant more.
Meanwhile, the 54-year-old revealed United will be without Eric Bailly for the next three games ahead of tomorrow’s clash.
“Bailly goes to surgery – the decision is made,” he said.
“I don’t say [he’s out] for the rest of the season but it’s for the next two or three months.
“But now we have [Phil] Jones back and we have [Chris] Smalling, even [Daley] Blind, so it’s a position we have good cover in but of course we’ll miss the player.”
He also revealed he would maybe rotate his squad for the game.
“A bit of recovering, a bit of rotation,” he added.
“I’ll change a few players from match to match because I think it is almost impossible for players to play all these matches in December and the beginning of January.”