The verdict in Maria Sharapova's appeal against a two-year doping ban will be announced by the Court of Arbitration for Sport (CAS) on Tuesday.
Five-time grand slam winner Sharapova was banned by the International Tennis Federation (ITF) in June following a positive test for the banned drug meldonium during January's Australian Open.
The former World No 1 from Russia is seeking to have her suspension wiped out or reduced.
She had called the ITF's ruling "unfairly harsh" as an independent tribunal had found that she had not intentionally violated anti-doping rules.
Sharapova, 29, admitted taking meldonium during the season's opening grand slam in Melbourne but said she had been unaware that it had been banned by the World Anti-Doping Agency (WADA).
Meldonium was added to WADA's list of banned substances at the start of the year after mounting evidence that it boosted blood flow and enhanced athletic performance.
Image: Maria Sharapova addresses the media regarding a failed drug test in Los Angeles, on March 7, 2016
Photograph: Kevork Djansezian/Getty Images
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