Louis van Gaal’s side took a step closer to Champions League qualification as they eased to an impressive win over the Lilywhites.
Goals from Marouane Fellaini, Michael Carrick and Wayne Rooney handed the Red Devils three points.
The victory kept United in fourth place in the Premier League table and just a point behind third-placed Arsenal heading into the final nine games of the season.
And former defender McGrath feels that the victory over the Lilywhites underlined United’s top-four credentials as the race for Champions League qualification hots up.
Speaking to talkSPORT, McGrath said: “Liverpool are the only team who can do a bit of damage to Manchester United.
“United are clicking into gear at the right time and are relaxed in the way they’re playing their football.”
United’s next game is a trip to Liverpool in the Premier League on Sunday as the Red Devils look to continue their bid for a top-four finish.
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