Holger Rune says it is 'crazy' how cleanly Novak Djokovic hits the ball after setting up practice sessions with him.
The 17-year-old is the world's top-ranked junior right now, and he is already close to breaking into the top 300 in the world.
He, though, appears to be in a real hurry to make his mark, and he approached the world number one to try to aid his development.
"I wrote to Novak Djokovic on Instagram, to be completely honest," Rune explained to TV Sport 2.
"[I wanted to check] whether he was in Monaco or in the area, because I saw that he had withdrawn from Miami. Then he wrote back."
Rune has now had a quick glimpse at Djokovic at close quarters, and he is understandably impressed with what he has seen.
"He hits the ball so clean, it's crazy. He does not miss many balls, so he is cool to train with.
"You get a good rhythm. You play lots of training sets. I hope he would like that (playing sets) so I can see if I can take a set from him."
Rune has just started to make his presence felt at ATP Tour events, and is one of just five players who are 17-years-old or younger who are in the top 1000 in the world right now - and he does not feel out of place.
"Now I have gained some experience at that level and know that the difference is not that big either," he said.
"There are some small things with the choices they make under different situations, but I believe I can at least play with him."
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