Novak Djokovic intends to come out fighting at this week’s ATP World Tour Finals and prove that rumours of his decline have been grossly exaggerated.

It seems a long time ago now that the all-conquering Serb was being tipped for a calendar-year grand slam, having won the Australian and French Open titles.

Andy Murray was his victim in both those finals but last week the Scot evicted Djokovic from the ATP’s world number one spot that he had jealously guarded for more than two years.

Since his first Roland Garros title in June, Djokovic has suffered some crushing blows; losing to Sam Querrey in the third round at Wimbledon, exiting the Rio Olympics in the first round and then being trumped by Stan Wawrinka in the US Open final.

He has not won a title since July and a first career loss to Marin Cilic in last week’s Paris Masters opened the door for a hungry Murray to steam through to the summit for the first time.

Niggling injuries have not helped Djokovic while rumours have abounded of emotional burnout.

The 29-year-old admitted that his early-season exploits had taken a toll, but said he was determined to end the year on a high and claim a fifth consecutive Tour Finals title.

“I’m here in London to crown this year with the best possible result,” Djokovic told reporters.

“I didn’t get to recover fast after the French Open. I had to dig deep and take some time to reflect be-cause it was an incredible achievement. It took a bit of time to get back on track but all in all it was a very good year.”

Djokovic, who has spent a total of 223 weeks as world number one during his career, can finish the year number one for the fifth time in the past six seasons if he wins in London.

He starts 405 points behind Murray who arrives on the back of a 19-match winning streak.

Djokovic’s hopes of climbing back above home favourite Murray have been helped by him being placed in the easier group.

He starts today against debutant Dominic Thiem and also plays French first-timer Gael Monfils and Milos Raonic.

Murray must contend with US Open champion Stan Wawrinka, Kei Nishikori and tomorrow’s opponent Marin Cilic.