Top coaches cast doubt on Kim's chances

Former world No 1 Kim Clijsters could struggle to compete with the top players when she returns to the WTA Tour in 2020 because the sport has become more physically demanding during the eight years she spent in retirement, Naomi Osaka's former coach said.

The popular Belgian won four Grand Slam titles before hanging up her racket for a second time in 2012, but in September the 36-yearold announced that she would come out of retirement again because of her love for the sport.

"It's hard to say what I expect from Kim as I don't know how she is physically. Tennis really got way more physical the last few years on the WTA Tour," said Sascha Bajin, who guided Osaka to two Grand Slam titles and was named 2018 WTA coach of the year, in an interview on the WTA website.