Novak Djokovic is capable of extending his record for holding the men's world No 1 ranking for most weeks to 400, believes Russia's Daniil Medvedev.
Djokovic, who won his 18th Grand Slam at the Australian Open last month, eclipsed Roger Federer's record on March 8 when he moved past the Swiss to hold the top ranking for the 311th week.
Russia's Medvedev, who will climb up to a career-best ranking of second on Monday, feels the 33-year-old is capable of extending his record over the coming months and years.
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"First of all, it's an unbelievable achievement," Medvedev said of Djokovic's feat at the top of the summit in men's tennis.
"I think in the world of tennis we talk about Grand Slams more than anything else. But this is also a small competition, I'm sure he's really happy about it. The way he's played, he's definitely capable of catching 400 weeks.
"We're going to try to not let him do this. I didn't manage to do anything in the Australian Open final, but that is what sport is about. Nobody is going to give him an easy pass, he's going to have to earn it."
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Medvedev, 25, will become the first player outside Djokovic, Roger Federer, Rafael Nadal and Andy Murray to be ranked in the top two since Lleyton Hewitt in 2005.
Only 11 of the last 68 Grand Slams have been won by players other than the 'Big Three' with ATP Finals champion Medvedev losing to Nadal in the 2019 US Open and to Djokovic at Melbourne Park last month.
"As I've always said about the Big Three, they are unbelievable. The records they have set [are] probably not going to be beaten maybe in 100 years," Medvedev said.
"It's very rare that you see this in sports. I don't think you can say that other players were not good enough in this era, it's just that they were unbelievable and there's nothing for others to be ashamed of."
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