LONDON • Andy Murray and Novak Djokovic are careering towards a Sunday showdown to decide their year-long battle for supremacy.

The rivals have matched each other stride for stride so far at the ATP World Tour Finals with Murray recording his second group victory on Wednesday after a come-from-behind 6-7 (9-11), 6-4, 6-4 win over Kei Nishikori in 3hr 20min.

Djokovic, replaced as world No. 1 last week by Murray after 122 weeks at the summit, won his group after notching his third straight win. The 12-time Grand Slam champion had beaten Dominic Thiem and Milos Raonic previously and rolled past first alternative David Goffin 6-1, 6-2 yesterday. Goffin was a late replacement for the injuredFrenchman Gael Monfils.

Murray is also on top of his group after claiming the scalps of Marin Cilic and Nishikori.

If he finishes top of his group, Murray will avoid meeting Djokovic until Sunday's final at the O2 Arena.

That is a thrilling proposition, given the final would decide not only the winner of this season's Tour Finals but also the holder of the prestigious year-end No. 1 world ranking.

Few would bet against them meeting in the final and TV executives will be positively praying for it.

"I mean, I think for the tournament, for everyone interested in tennis, that would probably be the perfect way to finish the year," Murray, whose 21-match winning streak has propelled him to the top of the rankings, told reporters.

"For me and I'm sure for Novak, both of our goals would be to try to win the event. For him, whether that's by beating me, someone else, or for me if it's winning against Novak or another player, it doesn't change for us as players.

"But (to play against each other in the final) would be the most exciting way to finish the year."

Not since 2001 has the No. 1 ranking changed in the final week of the season. That was when then-world No. 2 Lleyton Hewitt of Australia dethroned world No. 1 Gustavo Kuerten of Brazil in Sydney.

Should Djokovic, winner of the event for the past four years, and Murray meet on Sunday, it would be their first clash since Djokovic's French Open triumph in June.

Murray, though, has endured an exhausting schedule in the autumn, winning four consecutive titles. In addition, he used up precious reserves of energy in the victory over Nishikori - the longest match since London began hosting the tournament in 2009.

Murray was in the ice bath immediately afterwards and his powers of recovery will be put to the test over the next few days with Stan Wawrinka waiting today, followed by a likely semi-final with big-hitting Canadian Raonic.

"Who knows what's going to happen the next few days," Murray said.

"Just from my side I'm concentrating on trying to win my own matches. Make it as tough as possible for Novak to jump me."

REUTERS, AGENCE FRANCE-PRESSE

ATP WORLD TOUR FINALS

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