Roger Federer, 36, aims to become oldest world No.1 tennis player

Roger Federer will play in the ATP 500 event in Rotterdam  - if he makes it to semi-finals, he will have a chance to become the oldest world number one tennis player in history.

Top of the world: Federer, 36, becomes oldest number one

At 36, Roger Federer could become the oldest World No 1 tennis

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Roger Federer Reclaims the Title of World's Number One Men's

Roger Federer 'finally satisfied' after becoming oldest World No

Rotterdam Open: Roger Federer aims to become oldest World No 1

The Relentless Longevity of Novak Djokovic - WSJ

Roger Federer, at 36, Becomes Oldest World No 1 in Tennis History

Roger Federer returns to top of ATP rankings; oldest ever at 36 - ESPN

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