The 33-year-old was on a 21-match unbeaten run before the season came to a halt in early March, winning the ATP Cup with Serbia, an eighth Australian Open title and a fifth Dubai Tennis Championships crown.
"I feel bad for Novak. He had the momentum," Evert said on the French Open website.
"Everyone was saying, 'Is he going to win a Grand Slam? Is he going to win four in a row? He was playing awesome tennis and then all of a sudden (season stopped). He'll be an interesting story to see if he can get that momentum back."
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Djokovic, who recently returned to Serbia after being stranded in Marbella in Spain for two months due to lockdown, is organising an event that will be played across the Balkans and include Dominic Thiem, Grigor Dimitrov and Alexander Zverev.
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He said last month that he could win the most Grand Slam titles and become the longest-reigning world number one by the time he retires. Djokovic has 17 Grand Slams with Rafa Nadal on 19 and Roger Federer with 20.
The possibility of tennis being wiped out for the rest of the year has led former players and pundits to speculate whether the shutdown would be more detrimental to younger players or the game's dominant talents.
"I have a sneaky suspicion that the players that have been around for a long time, especially Serena (Williams), Roger, Rafa, I think they're going to dive right into it," said Evert.
"They're appreciating that they can be with their family. They're appreciating that they can rest their bodies. But they also know that time is not on their side."
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