Jim Courier has named Novak Djokovic the 'overwhelming favourite' to win the Australian Open, although he sees change coming in the ATP.
Djokovic boasts an imperious record in Australia, where he has won eight singles titles - more than any other man in history.
"I think throughout 2021, yes [someone outside of Djokovic, Nadal and Federer will win a major]," Courier told Wide World of Sports Radio.
"I don't think the old guard is going to sweep all the majors as they have in recent years.
"But I do expect that one of the old guards will win the Australian Open on the men's side. The women's field is quite a bit more open."
However, despite a belief that there are players on the verge of a major breakthrough, he doesn't expect it to come in Australia.
"Novak Djokovic is an overwhelming favourite given how many times he has lifted the trophy and how well he played last year," Courier added.
"He is rested, he's ready, he's had access to full practice in Adelaide and he's going to get a good match on Friday night. He's got everything lined up.
"The old guys aren't getting younger, so there will be some more chances for the younger guys.
"I can see some breakthroughs in other events later this year."
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