Novak Djokovic sets all-time record for weeks at No. 1

Novak Djokovic set a new landmark of 311 weeks as world number one on Monday, one week longer than Roger Federer whose tally of a record 20 Grand Slam titles is now firmly in the Serb's sights. With Federer turning 40 in August, the Serb has time on his side. He is also a year younger than Rafael Nadal who also has 20 majors.