Five-time Grand Slam champion Maria Sharapova will miss the Rio Olympics after her doping appeal was postponed until September by the Court of Arbitration for Sport (Cas).

She was given a two-year suspension in June after testing positive for the banned substance meldonium.

Sharapova appealed to Cas but both the 29-year-old Russian and the International Tennis Federation need more time to prepare their cases.

The Rio Olympics start on 5 August.

"Maria Sharapova and the International Tennis Federation (ITF) have agreed to defer the Cas decision until September 2016," said a statement.

"A decision is expected to be issued by 19 September 2016."

Sharapova tested positive for meldonium at the Australian Open in January.