Queens Park Rangers' midfielder Joey Barton will not be appealing against his 12-match ban handed out by the Football Association.
Barton was hit with the lengthy ban and fined £75,000 by an FA appointed independent regulatory commission on Wednesday following his red-card and subsequent incidents at Manchester City on the final day of the season.
After being dismissed for elbowing Carlos Tevez, he then kicked out at Sergio Aguero and clashed with Vincent Kompany as he left the pitch in the match on May 13.
QPR are now carrying out their own investigation into the incident, and said in
a statement: "Queens Park Rangers Football Club can confirm it has now started a full internal investigation in relation to Joey Barton's dismissal and subsequent events against Manchester City on the final day of the 2012/13 Barclays Premier League season.
"The QPR midfielder will not appeal against the independent regulatory commission's decision made on Wednesday and he and his team are now working in full cooperation with the club to assist in the internal investigation.
"The club expects the investigation to last at least two weeks.
"During this period, no one from the club or Joey Barton himself will make any further comment."
Barton received an automatic four-game suspension, with the additional eight matches a consequence of the manner of his dismissal.
The acts were condemned by the chairman of the regulatory commission, who stated: "There are rules of conduct that should be adhered to, and such behaviour tarnishes the image of football in this country, particularly as this match was the pinnacle of the domestic season and watched by millions around the globe."
It remains to be seen whether Barton will be part of the QPR squad for their pre-season tour to Asia in July.