Andre Agassi feels conditions are ideal for Andy Murray to "do some remarkable things" in 2017.
Novak Djokovic completed a career Grand Slam at last year's French Open but was deposed by Murray at the top of the rankings at the end of 2016 and lost his second-round match with Denis Istomin at the Australian Open this week.
With Roger Federer and Rafael Nadal still finding their way back from injury, Agassi thinks Murray is primed to add to his three major wins.
However, the American feels it would be foolish to write off Djokovic, whose form he believes could return just as quickly as it has faded away.
"Well, short of pulling out the crystal ball and guessing or sort of speculating, of course this is a heck of an opportunity for him [Murray], and he's certainly coming into his best years," said eight-time grand slam winner Agassi in a media conference.
"So when you line those things up, he has the runway or the platform to do some remarkable things.
"But, you know, you can't write off Novak this soon. Obviously there has been a turn of events that happened what seemed to be overnight, quite frankly.
"And going into 2016, I said on record I think he's going to win every one, and everything was looking pretty darn good. Then he woke up one day and it was different.
"I don't know what that is, but I know that it doesn't change overnight. I mean, things can be different, but if it changes that quick, it can change again.
"There is no reason in the world why it can't turn around as fast as it seemed to have left him.
"He's a heck of an athlete. In my opinion, one of the greats of all time. I give him high, high chance of coming back in a hurry.
"I don't think Andy is underestimating that Novak can show up at any time of the year and then be that dominant person that Andy was in the second half of last year.
"But, yes, I do think Andy has a heck of an opportunity in front of him and certainly the capability of putting up some big numbers."