Rio de Janerio: Switzerland’s Stanislas Wawrinka, also world number four, on Tuesday pulled out of the Rio Olympic Games 2016 due to a back injury, hurting Switzerland’s tennis medal hopes in the quadrennial sporting extravaganza.

Earlier, tennis great Roger Federer, silver medallist in 2012 London Olympics, had also withdrawn from the mega event and the rest of the season with a knee injury.

Withdrawal from the Olympics by Wawrinka, 31, means five of the top 10 of men’s tennis will not be seen in action in Rio.

As per reports, the world number four aggravated the injury in the Rogers Cup in Canada last week.

It would have been Stan Wawrinka’s third Olympics had the Swiss been able to avoid the injury. “I would like to have witnessed my third Olympic Games,” Wawrinka said. “This will not be possible now.”