However, the 12th seed has looked focused and close to his best form on his way to reaching a first Slam semi-final since the 2016 US Open. His US Open win past year was the first time he had won a Grand Slam outside of the French Open since winning the US Open in 2013.
Nadal, the 2008 and 2010 champion, will now face three-time victor Djokovic for the 52nd time with the Serb holding a 26-25 edge.
Djokovic has the slight edge at overall Tour-level at 26-25, but Nadal ended a seven-match losing streak against the Serb at Madrid previous year and also won their only meeting so far in 2018 in the semi-finals of the Rome Masters.
If Nadal wins to advance to the Wimbledon Men's Final, and historically he's never lost a Wimbledon Men's Semi-Final match, then he and Djokovic will be tied at 26 against one another.
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The 19-year-old becomes new Gunners boss Unai Emery's fifth signing, following hot on the heels of Lucas Torreira's arrival. Emery added that he wants "five captains" in his team, including current club captain Laurent Koscielny.
A year after the epic encounter between Nadal and Djokovic at the semifinal stage of Roland Garros, they took on each other in the final in 2014.
"He is one of the more complex players that I ever saw on our sport". Djokovic has had the air of a troubled man for most of this tournament and has been reluctant to talk about his serial flare-ups on court, against officials, fans, his box and himself.
He eventually finished off world number 53 Simon in the match's third tiebreak to move into his second Wimbledon quarter-final where twice champion Nadal is waiting.
Nadal had not dropped a set at the tournament until the quarterfinals where he fought back to defeat Juan Martin del Potro 7-5, 6-7 (7/9), 4-6, 6-4, 6-4 on Wednesday.
Nadal meanwhile revealed he expected a stern challenge from Djokovic despite having beaten him nine times in 13 matches at Grand Slams.
"I'm sorry for him", Nadal said in the press conference.
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This is not the final deal, as the detailed talks are yet to take place with the European Union on it. But many eurosceptic MPs are outraged at May's plan, and Davis's resignation letter was scathing.
Besides playing for the Wimbledon title, there was plenty of financial incentive for both players.
Friday's other semi-final pitches Anderson, the eighth seed who lost to Nadal in last year's US Open final, against ninth-seeded American John Isner.
Anderson is the first South African to make the last-four since Kevin Curren in 1983.
Rafael Nadal said he "feels sorry" for Roger Federer following his shock Wimbledon exit.
"I think I did a lot of things well".
"It´s not good for me".
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Harry and Meghan then toured the grounds with the presidential couple and their two Bernese mountain dogs, Brod and Sioda. As the sixth in line to the throne grimaced in mock pain, the Duchess stifled a laugh. "You know, one step at a time".