The 28-year-old had treatment on the upper part of his right leg while leading Czech Jiri Lehecka 3-2 in the first set and again two games later. He went on to lose the set 6-4 before telling the umpire he could not continue.

"It was a return when he served and volleyed and I don’t know if I felt it on the return or on the drop shot, but when I ran, I wanted to run faster and faster during the movement, and suddenly felt my hip blocked," Medvedev said.

"I couldn’t sprint, like when you strain a muscle or have a spasm, which is tough to know which of the two. Working with the physio, I asked if I could make it worse. He said ‘if it’s a tear, then yes. If it’s a spasm, no’.