Federer pokes fun at himself after reclaiming No.1

Amid all the plaudits after becoming the oldest World No.1 in tennis history, Roger Federer took a hilarious dig at his own age.

Federer, 36, sensationally reclaimed the ATP's top ranking after rallying past Robin Haase for a 4-6 6-1 6-1 to reach the Rotterdam Open semi-finals on Saturday morning.

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The 20-time grand slam champion, who celebrated a sixth Australian Open crown last month, will return to the summit for the first time since November 2012 when the rankings are updated on Monday, dethroning rival Rafael Nadal.

The Swiss legend is not only the No.1, but he is a funny guy too, as he showed with a brilliant tweet after the match.

"Apparently I'm the oldest tennis player with a #1 ranking. Somebody might have mentioned that to me already but I had a hard time hearing," Federer wrote on Twitter.

If someone had told Federer 13 months ago that reclaiming the No.1 ranking would require three more grand slam titles and three Masters 1000s, even he might have declared it mission impossible.

Fast forward a year and a bit, however, and the 36-year-old is back at the summit - the oldest man to make it since the ATP rankings came into being in 1973.

Few believed it was possible when he missed half of the 2016 season with knee and back problems.

But 14 years after he first achieved it, this one felt extra special, said the 20-times grand slam champion.

"Well it's a deep sense of satisfaction," Federer said.

"A lot of work went into it, coming back from the injury obviously. Just having had the year that I've had, winning three slams, that's what it took to get the ranking.

"I think I've shown resilience. I have a great team around me and we took a lot of good decisions in the last three years. I always planned for longevity and I never gave up that I could get back to winning ways, without ever dreaming of world number again to be honest, that was too far."

Incredibly, Federer first became No.1 in 2004 and on that occasion he stayed there for 237 weeks.

"The goal (this time) was to be World No.1 for a week, that's plenty for me," he said. "If it's more, great, I'll take it. If I play well, good things will happen.

"It's the ultimate achievement in our sport to get the number one ranking, it just doesn't come easy."

Federer now faces Italian Andreas Seppi in the semi-finals.

with agencies