?Former No. 1 Marat Safin says that No. 10 John Isner has the goods to be a top 5 player. "He should be inside the Top 5," said Safin, who is playing the ATP Champions Tour BNP Paribas Zurich Open this week. "It’s difficult to play against someone of his size. He serves way too big. When he has a good day it’s almost impossible to play against him. I just don’t think he is consistent enough, but he is already improving and in a few years he will get more experienced. He’s top 10 now and he definitely still has potential."
The Russian added that he doesn’t see any change in the current top four by year’s end. "I think at the end of the year [Novak] Djokovic will be No. 1," he said. "Then No. 2 will be [Rafael] Nadal, then [Roger] Federer, then [Andy] Murray. Not much will change. Djokovic is doing really well, and I think it’s going to be difficult for Nadal this year because Djokovic just keeps getting better and better and he has the confidence edge over him right now. And Federer is getting older, which is normal of course, and Murray has the game but he is still missing something for me."
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