Olivier Giroud has returned to an Arsenal front four entirely changed from Saturday's 5-0 victory over Arsenal.
Alexis Sanchez, Mesut Ozil and Alex Iwobi return to the starting lineup with Lucas Perez and Theo Walcott on the bench. Danny Welbeck is out of the squad with Shkodran Mustafi the only survivor from the FA Cup fourth round tie.
Watford have handed a debut to new signing M'Baye Niang, who is set to start on the left flank with Troy Deeney up front. Odion Ighalo has been left out of the squad ahead of a move to China.
TEAM NEWS
Arsenal starting XI: Cech; Gabriel, Mustafi, Koscielny, Monreal; Coquelin, Ramsey; Iwobi, Ozil, Alexis; Giroud
Substitutes: Ospina, Gibbs, Bellerin, Maitland-Niles, Oxlade-Chamberlain, Lucas, Walcott
Watford starting XI: Gomes; Cathcart, Kaboul, Prodl, Britos; Behrami; Janmaat, Cleverley, Capoue, Niang; Deeney
Substitutes: Arlauskis, Mariappa, Mason, Watson, Doucoure, Success, Okaka
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WHAT THEY SAID
Arsene Wenger: "We had never had so many players who could perform and score goals - certainly never.
"We had Bergkamp, Henry and after that Van Persie behind, Wiltord, Pires...it was not bad. They had the quality but now we have a large number."
In Pictures | Southampton vs Arsenal | 28/01/2017
Walter Mazzarri: "We have to react immediately. We have the chance to do it and obtain as soon as possible our first objective.
"This is what I wanted to say. We want to do it in the most positive manner."
