That is according to 2001 Wimbledon champion Goran Ivanisevic.
Federer has repeatedly dismissed suggestions he is thinking about retirement because he is still enjoying his tennis.
Nevertheless last week, Federer’s long-time agent Tony Godsick admitted the Swiss was in the “back nine” of his career but “hopefully not on the 18th hole”.
But with Novak Djokovic currently at the top of men’s tennis, Ivanisevic feels the Serbian will remain the most dominant figure and predicted Federer could soon call it a day.
“I do not think anyone can take Djokovic off the throne,” he told Croatian media.
“Federer, Djokovic, [Rafael] Nadal still dominates world tennis.
“But I think Federer will retire quickly, if not this year, next year.”
In January, Federer announced he intends to play on the clay this season.
And that led some to wonder if his decision was based on going on a farewell tour before retiring.
But the 37-year-old stressed that was not accurate.
“I thought of it, in isolation, do I want to play the clay or not? The answer was yes,” he said.
“This doesn’t mean this is my last clay-court season, whatever, or I had to play one more time before I retired. That was not the thinking.
“All I knew is after missing it for two to three years basically, my body was ready, I was ready, my schedule with the family, my schedule with the team was ready to do it again.
“This is when I opted to say, ‘It will be nice’.”
Roger Federer vs Fernando Verdasco start time
Roger Federer’s clash with Fernando Verdasco is due to start after 3pm (GMT).
Provided the second match on Centre Court between Gael Monfils and Marcos Baghdatis finishes on time, Federer and Verdasco will walk out onto the court at 3pm.