Jose Mourinho’s men head into the game looking to build on their impressive 3-0 win over Leicester at the King Power Stadium last weekend.
The Red Devils are currently in sixth place in the Premier League and 14 points behind leaders Chelsea after a mixed start to the season under new boss Mourinho.
However, the Portuguese coach will be hoping to see his team continue their march towards Champions League qualification by beating Watford on Saturday.
Writing in his column for The Daily Mail, Keown said: “This will be tight but I feel United will have learned the lessons Arsenal did not against Watford last week.
“Jose Mourinho is starting to realise he can gain ground on the teams above him.”
Manchester United are looking to break back into the top four this season after their disappointing fifth-placed finish last term.
The Red Devils did win the FA Cup in Louis van Gaal’s final season in charge, however, and could still defend their crown this term.
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