Ruud, Norway's No 1 tennis player, had never been inside the top 100 in the world when he started training at the Rafa Nadal Tennis Academy in Mallorca at the end of 2018.
Since moving to Spain, the 21-year-old has enjoyed a breakthrough year, winning his first main draw match at a Masters 1000 event and reaching his first ATP final when he was beaten by Christian Garin at the US Clay Court Championships.
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And the Norwegian has paid tribute to the impact of Nadal and his former coach, uncle Toni.
“I always felt like I’ve played with good intensity in my game and I need it to play well, but I’ve gotten that extra 10 or 20 per cent from being there,” Ruud said.
“That’s the small margin that can change whether you’re No. 10 [in the ATP Rankings] or No. 60. It’s not like they’ve changed my technique, but they’ve helped with all the strokes.
“It’s motivating to have Rafa there and even Toni [Nadal] coming to the practices and pushing you a bit more. You’re surrounded by very good players.”
He added: “I had split with my coach [in February 2018] and was training at home with my dad [former world No 39 Christian Ruud].
"It can be good, but I need to get out sometimes and train with other good players.
"They asked me if I wanted to try it out and Rafa is one of my biggest idols, so I didn’t see a point in saying no.
“My mother, younger sister and father came down.
"My sister also started full-time at the academy, playing every day and going to school there.”
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