Roger Federer has become the oldest world number one in tennis history courtesy of his victory over Robin Haase at the Rotterdam Open.
Federer lost the first set of the quarter-final 6-4, but bounced back to win the second and third 6-1 as the 36-year-old booked his spot in the semi-finals of the competition.
The victory saw Federer replace Rafael Nadal at the top of the rankings, and he was awarded a trophy for his achievement in the immediate aftermath of Friday's three-setter with Haase.
Federer, who has topped the rankings for the first time since October 2012, has taken the record away from Andre Agassi, with the American occupying the number one position in September 2003 at the age of 33.
The Swiss won his 20th Grand Slam earlier this year when he triumphed at the Australian Open.