Varvara Lepchenko has been cleared of any wrongdoing after testing positive for the now-illegal medication meldonium, the use of which left five-time grand slam winner Maria Sharapova banned.
International Tennis Federation anti-doping officials announced on Tuesday that the 30-year-old American had tested positive four times for the substance which was made illegal from January 1.
Sharapova, the length of whose ban is expected to be revealed in October, tested positive at this year's Australian Open.
But Uzbek-born Lepchenko was let off as she stopped taking meldonium prior to the start-of-year deadline, the statement said.
The ITF said meldonium was in the 30-year-olds system in decreasing amounts on January 7, February 1, March 1 and April 7.
In her appeal, the player said she stopped taking it just before Christmas.
Lepchenko was provisionally suspended in March but the ITF now says that she "bore no fault or negligence for the violation."
The Latvian-manufactured drug meldonium is popular in Eastern Europe and is used to increase blood circulation to the heart.
Sharapova, who said she took the drug for a medical condition, has said she was unaware that meldonium was to be made illegal, as the information was buried deep in lengthy emails sent to players by anti-doping officials.
