Samir Nasri has had his doping ban extended from six months to 18 months.
The former Manchester City and Arsenal midfielder, who is now a free agent, received his original sentence after he underwent intravenous treatment in Los Angeles which was in breach of the World Anti-Doping Agency's rules.
The sentence is backdated to July 1, 2017. Nasri last played for Turkish club Antalyaspor.
A UEFA statement said: "The UEFA Control, Ethics and Disciplinary Body's decision of 22 February 2018 is amended as follows:
"1. The player Samir Nasri is suspended for eighteen (18) months. This suspension will start running on 1 July 2017.
"2. The player Samir Nasri is allowed to return to training, with any football club starting from 1 November 2018."