Derby midfielder Stephen Pearson (knee) and striker Steven Davies (leg) may be included if they shake off their respected injuries in time.
Conor Doyle is back in the squad after returning from a training camp with the USA Under-20s.
Derby, with just one league win in seven matches and having been humiliated by non-League Crawley in the FA Cup this week, appear to be in freefall.
Little over a month ago the Rams were fourth in the table and in great form. They have since slipped to 13th, with Nigel Clough's job as manager reported to be under threat. And on top of that, captain Robbie Savage is considering an offer to join MLS side Vancouver Whitecaps.
County have managed only one away win this season against a current top-half team, and now is perhaps not the ideal time for them to be travelling to face the Championship's form side, who are fourth in the table and have won six matches in a row.
Watford continue to enjoy a great season, and could yet follow in the footsteps of Blackpool, who were also touted as relegation candidates before winning promotion via the play-offs. The Hornets boast the strongest attack in the second tier, with 47 goals netted in 24 games.
• Derby have won the last three matches between these clubs.
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• Watford have won only one of their last four home matches against the Rams (3-1 in May 2009).
• Watford are scoring, on average, every 3.28 attempts on target. It is the best ratio in the Championship.
• They have the best disciplinary record in the division, having picked up only 25 yellow cards.
• Hornets boss Malky Mackay has used only 20 players in league games this season - fewer than any other second-tier manager.
• Martin Taylor is set for his 250th career appearance and, along with Adrian Mariappa, has played every in minute of every Watford league game this term.
• Only 14 different players have netted league goals for Derby this season, giving them the joint shortest goalscorers list in the Championship, along with Burnley.
• Paul Green is in line for his 100th start for County, while Steve Davies could make his 100th league appearance.
Source: BBC Sport