Serena Williams' coach Patrick Mouratoglou praises former British number one Andy Murray for being "incredibly courageous" as he continues to try to get back to his career best.
Murray has only been able to play in three tour-level singles matches since the start of 2021 with coronavirus and a groin injury picked up ahead of the Miami Open in March hampering his progress further.
The 34-year-old hopes to return to the top of the men's game, but has only one tour win since last August.
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Mouratoglou admires Murray's bravery to keep coming back despite being unable to get a consistent run of matches together.
"Every time he feels 'wow, finally, I can start playing' then he has bad news about his physicality which stops him," he told Sky Sports.
"If he continues to stop and start all the time, it's very difficult because he makes progress and his fitness starts to be at a level. He needs competition.
"He starts, but then 'boom', he stops again and then he restarts almost from scratch because when you do nothing for a few weeks you lose all the benefit of what you've done.
"I think he's incredibly courageous to be honest, because he's had a lot of setbacks with his body and he's still here.
He shows how much courage he has, which we knew already, but also how much he loves the game.
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