Fitz Hall will serve a one-match ban after Watford successfully appealed against Gabriele Angella's red card in the club's 1-1 draw with Bournemouth at the weekend.
Angella, who signed for the club on a five-year contract from Udinese at the start of the season, gave Watford a first-half lead at Dean Court before being sent off later in the game in a case of mistaken identity.
Angella was adjudged to have denied a clear goalscoring opportunity when Lewis Grabban had his shirt pulled in the second half of the game.
But the culprit was in fact defensive partner Hall, who will now serve a one-match ban and will consequently miss Watford's FA cup tie with Manchester City this weekend.
Watford had lodged a further appeal against Hall's ban, but this was unsuccessful.