Watford will be without captain Gavin Mahon for the home match against Reading.
The influential midfielder must serve a one-match ban after collecting his fifth booking of the season in the 1-0 home defeat by Sheffield United on November 28.
The Hornets - bottom of the Barclays Premiership - welcome back veteran defender Chris Powell from suspension, but they are still without goalkeeper Ben Foster and forward Marlon King (both knee) as well as defender Clarke Carlisle (thigh).
Reading skipper Graeme Murty and forward Seol Ki-Hyeon both face late fitness tests on toe injuries.
Both missed training sessions and will only play at Vicarage Road with the aid of pain-killing injections.
Irish duo Stephen Hunt (hamstring) and Kevin Doyle (thigh) have been passed fit to play however, although the Royals are still without Bobby Convey (knee) and Dave Kitson (appendix).