Watford manager Malky Mackay is waiting on the fitness of key striker Danny Graham ahead of the visit of Leeds.
Graham - who scored four goals in the first two games of the season - was left on the bench for the midweek Carling Cup defeat to Notts County but came on for the final 15 minutes as the Hornets looked to find an equaliser.
But Graham pulled his groin in having a late shot on goal and is a serious doubt to face Leeds.
Mackay was also without captain John Eustace, Lee Hodson and Martin Taylor in midweek as they recovered from niggles and he is hoping they can all return against Simon Grayson`s side.
England Under-21 goalkeeper Scott Loach will also return to the starting line-up after he was rested against County.
Former Middlesbrough midfielder Josh Walker returns after being cup-tied on Tuesday night, while on-loan Birmingham man Jordon Mutch is also available again.
Leeds boss Grayson is set to make changes to his side.
Grayson opted to leave the likes of goalkeeper Kasper Schmeichel and on-loan forward Sanchez Watt on the bench for the 2-1 Carling Cup defeat to Leicester on Tuesday.
Both of those players are expected to return to the starting line-up, while midfielder Lloyd Sam, who was left out the squad completely on Tuesday, is also set to return.
Striker duo Billy Paynter (shin) and Robert Snodgrass (knee) are still ruled out as is long-term absentee Patrick Kisnorbo (knee).
Defender Ben Parker is back in training after recovering from an Achilles injury and may be included in the squad.
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