Only Rafael Nadal, with 22, has more men's majors.

All this in a year which saw him booted out of Melbourne and banned from travelling to North America over his continued refusal to be vaccinated.

With the exception of the Laver Cup in London, which doubled up as Roger Federer's farewell, Djokovic didn't play for the best part of three months after Wimbledon.

His "restart" in Israel came 16 years after he last played in the country.

Djokovic's determination not to waver over his vaccination stance meant he missed two of the year's four Slams, at the Australian and US Opens, and four of eight Masters in Indian Wells, Miami, Montreal and Cincinnati.

However, his win in Kazakhstan on Sunday allowed him to book a place in the ATP Finals for a 15th time -- only Federer (18) and Jimmy Connors and Nadal (16 each) have reached the season-ending showpiece on more occasions.

When the event takes place in Turin in November, the Serb will attempt to draw level with Federer as a six-time winner having been crowned champion in 2008 and every year from 2012-15.

Before then, Djokovic, the only man to have won all Masters titles twice, will defend his Paris Masters crown.

"I'm just very grateful and blessed to be able to play this well at this stage of my life," Djokovic said on Sunday. "You know, 35 is not 25."

When his roller-coaster year ends, Djokovic will hope he'll be able to fly to Melbourne and claim a 10th Australian Open despite the cancellation of his visa in January triggering a three-year ban on returning. The signs are encouraging.

"We are on the right track to win back all the top players," Tennis Australia chief Craig Tiley told The Australian newspaper last week.

"We are in a different time than nine months ago and I think the environment has completely changed. People are moving freely around the world again and we hope to have the best players here in January."