Watford have won an appeal against the red card shown to Lloyd Doyley in Tuesday's 3-2 win over Leicester City.
Doyley, 29, was sent off by referee David Webb, who adjudged the defender to be the last man when Jermaine Beckford was brought down late on.
But replays show that the challenge was committed by Adrian Mariappa, not Doyley, and that the Hornets seemed to have two covering defenders.
The club successfully appealed on the grounds of wrongful dismissal.
Boss Sean Dyche was also frustrated that substitute Carl Dickinson was not given time to join the wall to defend the subsequent injury-time free-kick.
Doyley will now be available for Saturday's Championship trip to Crystal Palace.