The Red Devils are in fifth place in the Premier League table and three points behind fourth-placed Manchester City ahead of the visit of the Hornets.
This will be hard against a decent Watford team, but I expect United to win
Louis van Gaal’s side have won their last three games in all competition as the Dutchman continues to hang on at Old Trafford despite speculation surrounding his future.
United teenager Marcus Rashford scored twice on his Premier League debut on Sunday as the Red Devils were 3-2 winners against bitter rivals Arsenal at Old Trafford.
Former Gunners midfielder Merson believes Van Gaal’s side will ease past Watford on Wednesday night in their pursuit of a top-four finish.
“Man Utd are really getting some momentum behind them and the goals of Marcus Rashford seem to have lifted the whole club and the fans,” Merson told Sky Sports.
“When one of your own scores a couple of goals, then the supporters walk away seeing a brighter future. Away from him, it feels like some of the others are now getting used to playing for a very big club.
“Anthony Martial was playing in front of small crowds at Monaco and now he’s learning his trade in front of 75,000 at Old Trafford.
“This will be hard against a decent Watford team, but I expect United to win.”
The Red Devils were 2-1 winners against Watford at Vicarage Road in the Premier League in November.
United host the Hornets on Wednesday before the Red Devils make the trip to West Bromwich Albion on Sunday afternoon.
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