Jonathan Hogg and Fitz Hall are unlikely to return in time for Watford's home clash against Huddersfield.
Midfielder Hogg and defender Hall have both missed out of late with hamstring injuries and the duo will continue to watch from the stands as Town, winless in 11 league games, come to Vicarage Road.
Tommie Hoban is also a doubt with an Achilles problem which ruled him of last weekend's 2-1 win at Middlesbrough.
Midfielder Connor Smith is definitely ruled out with a knee complaint.
Goalkeeper Manuel Almunia and midfielder Almen Abdi returned from injury to start at the Riverside and suffered no ill-effects.
Watford currently occupy the final play-off berth, two points clear of Millwall but four adrift of those above them.
Huddersfield winger Danny Ward is expected to return to contention for the game at Watford after a five-game injury lay-off.
Ward has been sidelined due to a knee injury, but could be back in action as Huddersfield chase their first league win in 12 matches.
Defender Joel Lynch is still out with a hamstring strain that has forced him to miss the last two games, while midfielder Oscar Gobern remains a long-term absentee following ankle surgery.
Manager Simon Grayson, who has no new injury or suspension problems, could recall Adam Hammill to his starting line-up after the on-loan Wolves winger stepped off the substitutes' bench against Birmingham last week to fire a superb stoppage-time equaliser.
Neil Danns made his debut last week following his loan switch from Leicester and is hoping to retain his place in the starting line-up, while fellow midfielders Keith Southern and Scott Arfield, plus defender Calum Woods and striker Lee Novak are all pushing for recalls.