Novak Djokovic is marking his 100th week at No. 1 in the ATP rankings.
The 26-year-old Serb is the ninth player to reach the milestone, joining Andre Agassi (101 weeks), Rafael Nadal (102), Bjorn Borg (109), John McEnroe (170), Jimmy Connors (268), Ivan Lendl (270), Pete Sampras (286) and Roger Federer (302).
Djokovic reached No. 1 in July 2011. He lost the top spot to Federer for three months in 2012 but regained it in November of that year.
Djokovic's bid to finish the year at No. 1 for a third straight time is under serious threat from Nadal. Djokovic has 11,120 points, while Nadal has 10,860.