Maria Sharapova has lodged an appeal to the Court of Arbitration for Sport (CAS) to challenge the two-year suspension imposed on her last week.

The five-time Grand Slam champion was provisionally banned by the International Tennis Federation (ITF) in March after testing positive for meldonium at this year's Australian Open. The former world No. 1 claimed to be unaware that meldonium had been added to WADA's prohibited list at the start of 2016.

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The ITF announced last Wednesday that an independent tribunal had handed out a two-year suspension to the Russian, backdated to January 26 — the date of her positive test in Melbourne.

Sharapova vowed to appeal what the 29-year-old considers to be an "unfairly harsh" ban.

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