The Hornets have not won a game since the start of October, picking up just four points from a possible 24 in their eight games since then.
The poor run of form has seen them slip to 12th in the Championship table, six points off the playoff places and just nine clear of the relegation zone.
Gianfranco Zola's side have lost their last four games at home and haven't scored at Vicarage Road since mid-October, losing to Leicester City, Bolton Wanderers and Yeovil Town without finding the net in front of their own fans in that time.
Sheffield Wednesday are in similarly poor form and find themselves in the relegation zone, just two points above bottom-placed Barnsley.
The managerless Owls have lost four of their last five matches, with the only positive in that time coming in the form of a shock victory over high-flying Leicester City.
Wednesday have only won two matches all season and are yet to taste success on their travels in the current campaign, with their winless away streak stretching back 12 games in the league and 13 in all competitions.
Sheffield Wednesday: WLLLWL
Possible starting lineups
Watford: Bond; Pudil, Ekstrand, Cassetti, Faraoni; Thorne, McGugan, Murray, Battocchio, Bellerin; Deeney
Sheffield Wednesday: Martinez; Palmer, Zayatte, Johnson, Mattock; Helan, Olofinjana, Coke, Maghoma, Wickham, Nuhiu
Sports Mole says: 2-0