Nadal vs Kyrgios - Four of the best in a testy history

Rafael Nadal and Nick Kyrgios will meet for a place in the Wimbledon final on Friday in what the Australian star claims will be "the most watched tennis match ever." Nadal leads their series 6-3. AFP Sport looks at four of their most memorable matches in a rivalry which has been thrilling and often testy.

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Struggling with physical ailment, Nadal appeared close to retiring mid-match in his quarterfinal against Taylor Fritz on Wednesday but somehow found the will to win in four hours and 20 minutes.

-- Just 19 and ranked at 144 in the world, the All England Club was treated to its first look at Kyrgios, a brash Australian wild-card. Nadal was the two-time Wimbledon champion and world number one.

However, his dreams of a third title were shattered on Centre Court as Kyrgios claimed a famous 7-6 (7/5), 5-7, 7-6 (7/5), 6-3 win. Kyrgios unleashed 37 aces and a total of 70 winners.

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"That's the biggest win of my career obviously, and that's something I'm never going to forget," Kyrgios said. "To have that under my belt, it's massive." US legend John McEnroe tipped Kyrgios as a future Grand Slam champion. "I think we have found the next guy in the men's game. I couldn't believe he could keep that up all match. He had this feeling about him that he absolutely believed that he would win," said McEnroe. -- After 2014, Nadal won three of the pair's next four meetings, but Kyrgios stunned the