His season had already provided several unforgettable chapters but Andy Murray saved the best to last as he eclipsed Novak Djokovic 6-3 6-4 to claim his first ATP World Tour Finals title and rubber stamp the year-end top ranking on Sunday.

Against a man who has so often been his nemesis, Britain’s golden boy Murray produced a relentless display to claim a ninth title of a year which included a second Wimbledon crown and Olympic gold in Rio.

Murray’s play in the winner-takes-all season climax was all the more remarkable as a day earlier he looked on the point of mental and physical exhaustion after taking almost four hours to subdue Milos Raonic in the semi-final.

“It’s very special playing against Novak in a match like this, we’ve played grand slam finals and at the Olympics before, but I am very happy to win and to be world number one is very special. It is something I never expected,” Murray said.

Murray’s win came two days after older brother Jamie was crowned number one doubles pair with Brazil’s Bruno Soares and a year since Dunblane’s finest led Britain to the Davis Cup title.

Djokovic had won 22 of his past 23 matches at the Thames-side venue, but the cracks that have appeared in his game since completing a career slam by beating Murray in the French Open final returned after a trouble-free route to the final.