The Red Devils will be looking to record a third successive Premier League win following a dramatic 3-2 victory over derby rivals Manchester City at The Etihad last weekend.
The Citizens were leading 2-0 but Paul Pogba scored twice to level the derby clash before Chris Smalling netted a winner to complete their comeback on Eastlands.
Manchester United are in second place in the Premier League table and have a four points lead over Liverpool FC and Tottenham Hotspur.
West Brom, on the other hand, are rooted to the bottom of the Premier League table and 10 points from safety with five games to go.
Former Arsenal star Merson believes Manchester United won’t have any trouble seeing off the challenge of West Brom at Old Trafford on Sunday afternoon.
“What score do you want?! Man Utd don’t blow teams away but I think they will here,” Merson told Sky Sports.
“West Brom are all-but relegated, Man Utd have just beaten City away, I think Jose Mourinho surely has to let them off the leash here. When he does that they can play.
“I hope West Brom put on a show for Darren Moore because I think he has a chance of getting the job if they do well, but I can’t see them getting anything from this game.”
Manchester United are in second place in the Premier League table but 13 points adrift of Manchester City after a one-sided title race.
The Red Devils signed Chile international Alexis Sanchez in a swap deal from Arsenal in the January transfer window.
Manchester United can win the FA Cup this season but the Red Devils need to beat Spurs in tbhe last four.
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