Novak Djokovic has passed on his congratulations to Andy Murray after the Briton replaced him as the no. 1 force in men's tennis.
Murray rose to the summit of the ATP rankings on Sunday (6 November) after Milos Raonic withdrew from Saturday's Paris Masters semi-final with injury.
The 29-year-old celebrated his achievement by winning his eighth title of the year in the French capital on Sunday and now heads to the season-ending World Tour Finals in London as top seed.
An alarming drop in form from Djokovic during the second half of 2016 allowed Murray to close the gap and replace him as the sport's dominant force but the Serbian has passed on a heartfelt message to his rival, also promising to return to his blistering best.
"Congratulations Andy Murray! Very well deserved and hard fought milestone," Djokovic wrote on his Facebook page.
"Your dedication and passion has paid off and I am really happy to be in the same era with you. As to all my #NoleFam, thank you for being there for me. I am working hard and will see you all in London. I am always game when it comes to good challenges and (the) final eight is exactly that. See you in a few days."
Djokovic could yet reclaim top spot at the ATP Finals. Murray has been handed a potentially troublesome draw and will face Stanislas Wawrinka, Kei Nishikori and Marin Cilic in the round-robin stage at The O2 Arena, knowing he must match the performance of the Serbian to ensure he ends 2016 top of the standings.
Djokovic, who sat atop the world rankings for 122 weeks, secured a more favourable draw against Milos Raonic, who remains an injury doubt, Gael Monfils and Dominic Thiem. Djokovic has won the last five consecutive season-ending competitions in London.
The Australian and French Open champion will begin his campaign against Thiem on Sunday (13 November) with Murray in action the following day against Cilic.