That is the shock verdict of three-time Grand Slam champion Tracy Austin.
Federer, who started the Rotterdam Open just 155 points behind Rafael Nadal, could top the ATP rankings should he overcome Robin Haase in the quarter-finals later today (6.30pm).
Should he prevail, he will also become the oldest No 1 in the men’s game since Andre Agassi, who was 33 when he achieved that feat.
Federer has started the season in fabulous form and he lifted his 20th Grand Slam title at the Australian Open last month with victory over Cilic.
While Federer continues to defy the test of time with his movement around court, Austin thinks there is one player from the chasing pack that could catch up.
During a studio debate as to who will finish the year as World No 1, Austin picked Cilic.
However, she admitted his consistency could hold him back from achieving his goal.
“Maybe Cilic might come forward. He’s No 3 and he’s only 710 points behind Roger,” Austin told Tennis.com.
“Got to two finals last year. Seems to be getting better and seems to be maturing.
“His consistency is what I worry about.
“It’s a really fascinating concept to figure out in February.”