After a cagey first half, United took a deserved lead early in the second, through Casemiro’s seventh goal of the season, before the visitors equalised through Ross Barkley.
However, Matheus Cunha put United back in front inside the final 20 minutes, after being teed up by Bruno Fernandes, whose two assists on the afternoon took his tally to 16 for the season; a best-ever figure recorded by a United player in a Premier League campaign, still with eight games to play.
Benjamin Sesko came off the bench to make sure of the victory, keeping the Reds in the third and in a promising position to secure UEFA Champions League football next season.