Serbia's Novak Djokovic hits a return to Britain's Andy Murray during their men's singles tennis match at the ATP World Tour Finals in the O2 Arena in London on Wednesday.

London - Novak Djokovic closed in on a last four berth at the ATP World Tour Finals after squeezing past Britain's Andy Murray in the latest chapter of their evolving rivalry on Wednesday.

Once again there was barely a cigarette paper between the two 25-year-olds as Djokovic chiselled out a 4-6, 6-3, 7-5 victory to take command of Group A at the season-ending showdown.

Apart from the opening set when world number three Murray could do no wrong, the quality did not reach the heights of their clashes at this year's Australian Open semi-final or the US Open final, but it was rivetting fare all the same.

Some of the rallies resembled high-speed chess as first Murray held sway, then Djokovic got on top before holding off a late Murray fightback to seal victory in two hours 34 minutes.

It was his fourth victory over Murray this year with the other three clashes going the way of the Scot, most notably in an epic five-setter in the final of the US Open when Murray became the first British man in 76 years to win a grand slam.

“The last two minutes of the match were about what decided it,” Murray, who can still qualify for the semi-finals if he wins his final round-robin match against Jo-Wilfried Tsonga on Friday, told reporters when asked where the match swung.

“He broke at 15-40 and then I had 15-40 in the next game and didn't break,” added Murray of a strange finale to a clash he seemed to have under control after taking the first set.

A miserly Murray dropped only three points on his serve in that opener, offering Djokovic no way into the match.

However, Djokovic has not ended a second consecutive year at No.1 in the rankings for no reason and he bided his time.

With Murray still bossing the rallies Djokovic had to produce a moment of magic to avoid dropping his serve at 1-1 in the second set, bravely landing a drive volley flush on the intersection between baseline and sideline.

He then broke Murray for the first time in the next game when his opponent missed a volley and the momentum shifted his way as the almost inevitable decider loomed.

A terrible service game from Murray gifted Djokovic a break of serve and he then had to scramble to avoid a double break before launching a spirited late fightback.

When Murray levelled at 4-4 he looked favourite to win but a lapse at 5-5 allowed Djokovic the chance to serve for the match and he seized it, battling back from 15-40 to seal victory.

“Another great match. Another great performance from both of us,” was Djokovic's assessment.

“I didn't expect anything less, other than a tough match that went down the wire and was decided in the last point.”

“We have a great rivalry that hopefully will develop even more in the future,” added the five-times grand slam champion.

Fans around the world will surely hope so.

Tsonga takes on Tomas Berdych later on Wednesday with both players looking for their first win. - Reuters