"The player is not currently banned from playing. However, after consulting the club, Darijo Srna has taken the decision not to play until the matter has been resolved so he can concentrate on preparing his defense," FC Shakhtar Donetsk said in an official statement on September 22.
The club says it respects and supports Darijo's decision and is confident that the player will clear his name.
Read alsoShakhtar beats Napoli in Champions LeagueAt the same time, FC Shakhtar Donetsk stresses it considers the use of doping in sport unacceptable and reaffirms its adherence to the idea of combating doping.
"We are unable to comment on the matter any further at this stage due to the confidentiality of the legal proceedings," the statement said.
Srna in turn issued a statement saying that he was notified by the National Anti-Doping Centre of Ukraine (NADCU) on September 18, 2017, that a prohibited substance was reportedly found in an out-of-competition sample he provided on March 22, 2017.
"Firstly and most importantly, I would like to make it clear that I have never knowingly or intentionally taken any prohibited substance, nor unfairly intended to gain a competitive advantage," he said.
"I am investigating the possible source of the substance and am cooperating fully with NADCU in this respect. In order to focus on my defense and avoid any undue distractions for the team, I have made the decision to refrain myself from playing until the ongoing legal proceedings have been resolved. I will now be focused entirely on clearing my name and reputation," he said.
"Due to the confidentiality of the legal proceedings, I am not able to comment any further at this stage," he added.