An inspired Dimitrov battled through cramp and milked the raucous support of the fans at the clay Masters event in the Spanish capital, producing some breathtaking shots to oust the top-seeded Serbian in the second round and claim by far the biggest win of his career.
The youngest of the six players aged 23 or under in the top 50, he appeared close to tears as he embraced his coaching team after the three-hour slug fest at the Magic Box arena before seeming oddly underwhelmed at his post-match news conference.
"I mean, of course it's always great to win a match like that," he told reporters.
"Of course he's the number one, of course it's a great feeling," he added.
"But it's just the beginning of the tournament. It was just second round if you think about it, so you just got to get ready for the next matches and make sure that you can do that again."
The offspring of a volleyball-playing mother and a tennis coach father, Dimitrov began playing aged five and his hero growing up was Pete Sampras.
He attracted the attention of Federer's former coach Peter Lundgren after winning junior titles at Wimbledon and the U.S. Open in 2008 and it was Lundgren who famously made the comparison with the Swiss maestro.
His current coach is Mikael Tillstrom and his work with the Swede and his team seems to be paying off.
He reached the final in Brisbane in January, losing to world number three Andy Murray, and made his first Masters quarter-final in Monte Carlo last month, where he took a set off clay king Rafa Nadal.
Asked if beating Djokovic was confirmation that he had the talent to be a top player, he said:
"First of all, I think that talent doesn't really win matches. It helps you win matches, but doesn't win the match itself.
"Of course this has been what I've been working for, to play matches like that, and why not win them?
"Today was one of those days that I felt good on court. I felt I had enough hours of practice in the weeks before. I felt that I could actually hang with Novak the whole match."
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