Sunderland defender Phil Bardsley will serve a four-match ban after the club decided not to contest a Football Association charge of violent conduct.
The 26-year-old Scotland international was charged on video evidence after appearing to stamp on Chelsea's Juan Mata during Saturday's 2-1 home defeat at the Stadium of Light.
Bardsley will miss the Black Cats' Barclays Premier League clashes with Stoke, Norwich, West Brom and Arsenal because of what is effectively his second sending-off of the season.
A club statement said on Wednesday: "Sunderland has confirmed it will not be appealing the Football Association's charge against Phil Bardsley following the Barclays Premier League fixture with Chelsea on Saturday September 10.
"The FA yesterday advised that the defender would be cited retrospectively following an incident involving Chelsea's Juan Mata during the first half of the fixture at the Stadium of Light.
"The Scotland international will face a four-match suspension which comes into effect from Sunday's game against Stoke City at the Stadium of Light."
Bardsley was sent off for two bookable offences during the 1-0 home defeat by arch-rivals Newcastle on August 20.
Bardsley's absence represents a fresh blow for manager Steve Bruce, who saw record signing Asamoah Gyan head for United Arab Emirates side Al-Ain on loan for the rest of the season just hours before kick-off on Saturday.
Bardsley has been one of Bruce's most dependable men in recent times, operating largely as a left-back rather than in his favoured position on the right last season.
He returned to the right against Chelsea with Republic of Ireland international John O'Shea missing because of a calf problem, and with O'Shea fighting to be fit for Sunday's visit of the Potters, the manager's options look to be limited.
Ahmed Elmohamady has played there in the past, while Michael Turner's return to fitness could mean Wes Brown's versatility may prove a bonus.
Sunderland head into the game still looking for their first victory of the season and with Bruce's critics growing increasingly vociferous.