Chelsea boss Maurizio Sarri makes four changes to the team that started the 1-1 draw at Eintracht Frankfurt on Thursday.
Eden Hazard and Gonzalo Higuain return to the starting XI. Mateo Kovacic comes in for Ruben Loftus-Cheek in midfield and Marcos Alonso takes over from Emerson Palmieri at left-back.
Chelsea (4-3-3): Arrizabalaga; Azpilicueta (c), Christensen, David Luiz, Alonso; Kante, Jorginho, Kovacic; Pedro, Higuain, Hazard.
Subs: Caballero, Zappacosta, Cahill, Barkley, Loftus-Cheek, Willian, Giroud.
Watford (4-2-2-2): Foster; Femenia, Mariappa, Cathcart, Holebas; Doucoure, Chalobah; Hughes, Pereyra; Deulofeu, Deeney
Subs: Gomes, Janmaat, Masina, Kabasele, Cleverley, Success, Gray.
The referee is Paul Tierney.
Come on Chelsea!!!