Coach Gilles Cervara has told Daniil Medvedev to stop joking about his poor record on clay and start improving it.
Medvedev is the world number three, a multiple Masters winner, and he has also reached two Grand Slam finals.
However, every final he has ever reached, with the single exception of Barcelona in 2019, has been on a hard court.
Meanwhile, he goes into this year's French Open without a single victory to his name at Roland Garros despite playing it four times.
That included last year when he was the number four seed, yet still lost out in the first round to Marton Fucsovics.
Medvedev has mostly kept his sense of humour about his poor record on clay, but Cervara says the time has come to stop the joking.
“He has a lot of room for improvement on clay," Cervara told Tennis Majors.
"He’s never won a match at Roland Garros. We’ve been seen joking about it before, which is good for not letting the pressure get to us, but I don’t feel like joking much anymore.
“We’ll do Madrid and Rome. These tournaments will reveal things that will allow us to discuss and choose what will happen just before Roland Garros - for our training and possibly to play another tournament.”
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