Roger Federer became the oldest world number one on Friday when the 20-time Grand Slam title winner reached the semi-finals of the Rotterdam Open.
The 36-year-old Swiss overcame an early setback to beat Robin Haase of the Netherlands 4-6, 6-1, 6-1 and will replace old rival Rafael Nadal at the top of the rankings.
"What an amazing run it's been, to be number one again means a lot to me," Federer said.
"This is incredibly special, I'm so happy. I didn't really think I could get back to number one, this is a significant moment in my career."
Federer surpasses Andre Agassi, who held the top spot aged 33 years and 131 days in 2003, as the oldest man to claim the world number one spot.
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According to the Sky Sports, the Swiss great secured his spot in the history books and the last four of the tournament with a 4-6 6-1 6-1 victory against Haase on Friday.
The 36-year-old became the oldest No. 1 male player, surpassing eight-time Grand Slam winner Andre Agassi, who holds the record at 33 years since September 2003.
ANI
