Lukaku avoided retrospective action from the Football Association after an incident involving Brighton & Hove Albion's Gaetan Bong at the weekend, and Jose Mourinho has decided to keep faith in the Belgian who continues to struggle in front of goal.
Mourinho has made two changes to his starting lineup, with defender Marcos Rojo being handed his first league start since April due to a serious knee injury and Jesse Lingard being included in midfield.
Watford: Gomes; Mariappa, Prodl, Kabasele; Femenia, Cleverley, Doucoure, Zeegelaar; Hughes, Richarlison; Gray
Subs: Karnezis, Wague, Janmaat, Capoue, Carrillo, Pereyra, Deeney
Manchester United: De Gea; Valencia, Lindelof, Smalling, Rojo, Young, Matic, Pogba, Lingard, Martial; Lukaku
Subs: Romero, Darmian, Herrera, McTominay, Mata, Rashford, Ibrahimovic
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