With three of the four grand slam titles and a record six Masters Series crowns scooped up in a year of domination, Novak Djokovic could be forgiven for using the ATP Tour Finals in London as a well-earned lap of honor.

Not a bit of it.

The 28-year-old world number one's appetite for stomping all over his supposed rivals is insatiable.

Serbian Djokovic will start as overwhelming favorite to claim a fourth consecutive title at the year-ender, having won 14 matches in a row at the Thames-side venue where last year ended in anti-climactic fashion as Roger Federer withdrew from their showdown with a back injury.

The numbers Djokovic has compiled this year surpass even his dominant 2011 campaign when he also won three majors.

He will arrive with a 78-5 win/loss record and on a 22-match winning streak, stretching back to his defeat by Federer in the Cincinnati final in August.

He has owned the number one ranking since July 2014 and he will end the year there for a fourth time -- the same as John McEnroe and Ivan Lendl.

"In terms of the grand slams, this has been a better season than 2011," Djokovic, who would have won all four but for an inspired Stanislas Wawrinka in the French Open final, said in an interview with Sport Magazine.

"It's about the overall feeling of my game -- the way I play and the way I feel on the court. I'm a more complete player physically; technically I've improved since 2011, and mentally I'm more stable."

Worryingly, no one seems to have a clue how to stop him.

World number two Andy Murray, who is juggling the Tour Finals on home soil with trying to win the Davis Cup for Britain for the first time since 1936 the week after, has lost 10 of his last 11 matches against Djokovic.

Murray failed to survive the round-robin stage last year when he was demolished by Federer.

Since losing to Djokovic in last week's Paris Masters final he has practiced mainly on clay in readiness for Davis Cup duty in Ghent.

He was, however, placed in the easier-looking group in Thursday's draw, avoiding Federer and Djokovic.

Federer, 34, always puts on a show in London -- having reached the final four times since the event moved from Shanghai in 2009, winning twice.

Unlike last year when several new faces qualified, this year's eight are the usual suspects, with Japan's Kei Nishikori the least experienced on his second appearance.

A rejuvenated Rafael Nadal is back after missing out last year through injury and while still not quite the formidable foe he was at his peak the Spaniard will relish testing his improvement against Murray and Wawrinka in group play.

David Ferrer and Tomas Berdych will do well to reach the semis, Wawrinka could be the dark horse after reaching the last four in 2013 and last year when he lost an epic to Federer.