Top-20 player Belinda Bencic says on Twitter that she is pulling out of the Rio de Janeiro Olympics, another blow to a Swiss tennis team that also lost Roger Federer this week.

Bencic, who is No. 16 in the WTA rankings, says Wednesday that she is "not completely ready" to compete at the Summer Games, although her injured left wrist has healed.

The wrist problem forced the 19-year-old Bencic to quit during her second-round match at Wimbledon on June 30.

Federer announced Tuesday that he would sit out the rest of the season to protect his surgically repaired left knee.

One person affected by both withdrawals is Martina Hingis, who was expected to play doubles with Bencic and mixed doubles with Federer at the Olympics. Hingis' mother coaches Bencic.