Stan Wawrinka will take time away from the game to try to cure his left knee problem after crashing out of Wimbledon in the first round.

On a day when Andy Murray and Rafael Nadal breezed into round two, fifth seed Wawrinka was the victim of the opening day's big upset, losing 6-4 3-6 6-4 6-1 to Russian Daniil Medvedev.

Nadal could no doubt sympathise with the Swiss, who he dismissed so brutally in the final of the French Open three weeks ago.

A left knee issue Wawrinka thought was behind him flared up on the grass and he looked uncomfortable throughout his Centre Court ordeal.

The 32-year-old said: "It's not something new, but something I had in the past, the end of last year and also in Australia.

"Since I had that problem, this was the first time I'm playing on grass. Apparently grass is not the best surface for my knee.

"I need to figure out exactly what's the problem now, what I'm going to do, and come back on the tennis court when I am feeling without any pain."