Crystal Palace could be without the injured Scott Dann, who missed the midweek defeat at Manchester United along with several other first-team regulars.
James McArthur made his comeback from an ankle injury at Old Trafford but he is unlikely to start on Sunday.
Watford also rested players in midweek and Troy Deeney and Odion Ighalo are among those expected to return.
Nordin Amrabat is suspended following his sending off at West Ham.
MOTD COMMENTATOR’S NOTES
Simon Brotherton: “This is a match that brings back memories of a tense Championship play-off final between the sides three years ago, which was decided in Palace’s favour thanks to a Kevin Phillips penalty in extra-time.
“This game could be just as tight and looks equally hard to call, not least because both sides have struggled for form since the turn of the year. Palace have won just one of the last 15 in the league, Watford only two more.
“Both Premier League meetings this season resulted in away victories, so at least each set of supporters will turn up feeling they’ve got a great chance of getting to the final.”