Roger Federer and Rafael Nadal will resume arguably the greatest rivalry in tennis when they face each other in the Wimbledon 2019 men’s singles semi-finals on Friday.

This will be the 40th time the two legends will play each other on the ATP Tour, with the Spaniard leading his Swiss rival 24-15 in their career head-to-head.

Eleven years after the epic final, the timeless Federer-Nadal show makes its way to Wimbledon again

Nadal had beaten Federer in their last meeting – the French Open semi-finals a month ago. While the left-hander will take confidence from that straight-sets victory, his coach Carlos Moya believes the upcoming match on the All England Club’s grass court will be an entirely different affair.

“Defending and second-guessing on grass are more complicated. The one who strikes first is the one who has more options to win the point. In the end, the grass rewards aggression,” Moya told ATPTour.com on the eve of the highly-anticipated match.

“You always have to try to play in favour of the surface on which you compete. On clay, you can work the point more and afford not to take as many risks. It’s the opposite on grass. Rafa is doing very well at dictating play so far. Against Federer, he doesn’t need to change anything, since his grass-court play is perfect the way it is. We know Rafa is set to face a very tough opponent, but he should not change anything.”

Moya, who hasn’t traveled for the Championships and is currently back home in Mallorca, is confident Nadal can defeat any player on any surface. “There is no favourite. When he plays like this, Nadal is not inferior to anyone,” he said. “The outcome is wide open. When he’s at full strength, Rafa is almost always the favourite, regardless of the surface. I don’t feel he’s inferior to anyone, honestly.”

The 42-year-old, who is a former World No 1 and the 1998 French Open champion, reckons the Federer-Nadal rivalry is probably the most important rivalry in the sport’s history. “Rafa sees Roger as a lifelong rival, a special opponent.

“Their rivalry goes back a long way, many years and a lot of history now. It is probably the most important rivalry in the history of tennis. All that doesn’t matter to Rafa when they meet. He’s just looking for ways to inflict damage on Federer.”

Moya reckons Nadal will be the favourite if the match goes to five sets, but he’s quick to remember the 2017 Australian Open final where Federer emerged victorious after the contest went all the way.

“Historically it should benefit Rafa, but we know what happened in the final of the Australian Open in 2017. Nadal understands that the match is going to be decided by fewer and fewer shots, even if that’s not what he wants. Shorter rallies, shorter points, shorter matches, less wear and tear,” said Moya.

“Something else is clear: If Federer does not want a long, drawn-out match, there won’t be a long, drawn-out match. Whoever is more aggressive will have the upper hand in dictating the rhythm and flow of the match. Whoever goes on the attack in an ultra-aggressive manner will emerge victorious.”