Novak Djokovic
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Retired tennis player Sebastien Grosjean says current tennis stars Roger Federer, Rafael Nadal and Novak Djokovic are aliens because of what they have achieved in their field.

Federer has won 20 Grand Slam titles, which is the highest by any Men's Singles player in the open era. Behind him in the list is Nadal with 17 Grand Slam titles and then, Djokovic is third with 15 Grand Slam titles.

Djokovic added one more to the tally of 15 Grand Slam titles after defeating Nadal at the 2019 Australian Open final.

Grosjean says the new Australian Open winner deserves the same praise and respect as the way Federer and Nadal receive.

"When a guy dominates as Novak does, you need to admire and respect him. You should praise him, like Roger and Rafa. They're the exception. They're aliens. I find this exceptional," Grosjean said during an interview with LEquipe.

Sebastien Grosjean was appointed as the French team's Davis Cup captain in December 2018.

He said that talking to the players like Gilles Simon, Gael Monfils, Jeremy Chardy, Pierre-Hugues Herbert and Benoit Paire is not a 'priority' for him until the end of the 2019 Montpellier Open, which was concluded last weekend.

Journalist Peter Bodo of ESPN says neither of Federer, Nadal or Djokovic is considered as GOAT [greatest of all time].

"Shortly after Novak Djokovic mastered Rafael Nadal at this year's Australian Open final to lock down his 15th Grand Slam singles title, the simmering GOAT debate came to a boil again," Peter Bodo of ESPN said.

"We immediately asked whether we need to start thinking about the top-ranked Serbian as the best ever. But it raised another interesting question: Is it really possible the three greatest players of all time are active right now?

"Sure, it's feasible, but it's highly unlikely. This embarrassment of generational riches -- Roger Federer owns 20 major singles titles, Nadal has 17, just two more than Djokovic -- suggests our metrics for determining the GOAT are far too simplistic.

"The cumulative success of this trio is so overwhelming that it makes you wonder if it's even fair to compare them to their predecessors. If you acknowledge that, the GOAT debate changes drastically."