New Delhi, Nov 20 : The 24-time Grand Slam champion Novak Djokovic on Monday begins a record-extending 400th week as No. 1 in the men's rankings, more than 12 years after he first rose to the top. Djokovic, who clinched ATP Year-End No. 1 for a record eighth time during the ATP Finals, claimed a record-breaking seventh season finale title Sunday in Turin to welcome in his 400th week at the top in style. "It's a pretty good achievement, 400 weeks at No. 1. It's never been done in history. Someone will eventually break it, but hopefully it stays there for a long time," aid Djokovic of this landmark on ATPTour.com. The Serbian was guaranteed to hit this milestone following his opening round-robin win over Holger Rune at the ATP Finals a week ago. The win earned him the year-end No. 1 ranking for a record eighth time and extended his all-time record for the most weeks at No. 1. The 36-year-old has surpassed several iconic names across both tours including Steffi Graf (377), Serena Williams (319), Martina Navratilova (332), and one of his longtime rivals Roger Federer (310) for the most weeks at No. 1 and by some margin. In February, Djokovic broke Graf's record of 377 weeks to become the all-time men's and women's leader, having passed Roger Federer's 310-week mark in 2021 for most weeks at No. 1 by a man. The Serb will have many more milestones ahead of him in 2024. He is just two trophies away from 100 career titles. With 1,086 victories, he is likely to become just the third man in history to pass 1,100 match wins after Jimmy Connors, Roger Federer. Moreover, he will look to add to his record 24 Grand Slams (including 10 Australian Opens) and 40 ATP Masters 1000 titles. /IANS