The Hornets drew 1-1 at Brighton & Hove Albion in their last match before the winter break, leaving them in 19th place with only Norwich City below them as they look to secure a sixth straight season in the top flight.
We've taken a detailed look at Nigel Pearson's side, ahead of their visit to Old Trafford...
TEAM NEWS
Winger Ismaila Sarr and right-back Kiko Femenia are in contention to face United after returning from thigh injuries. Long-term absentee Daryl Janmaat could make his comeback at the end of the month but this weekend's game will come too soon for him.