Roddick has not yet qualified for the World Tour finals in London next month.
Victory guaranteed Murray, 23, his place in next month's season-ending World Tour Finals at London's O2 Arena.
That tournament begins on 2 November, with the end-of-season ATP World Tour Finals in London following three weeks later.
The 20-year-old Azarenka has now lost five of her eight WTA Tour finals.
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Last year's champs, Daniel Nestor and Nenad Zimonjic, split after the tournament and have been playing at this year's tour finals with new partners.
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After Paris, the top eight ranked men's and doubles players head to their ATP World Tour Finals in London in the last week of November.
He became the first American since Roddick to reach three consecutive ATP Tour finals, and has launched himself up the world rankings to 26th.
Men's doubles tennis reaches its high-water mark at the year-end ATP World Tour Finals in London, where the sport's top players take center stage each day.
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He is closing on Roger Federer at the top of the rankings, heading into the Paris Masters and the ATP Tour Finals in London next month.
But Murray, who has been plagued by the problem over the last six weeks, is focussed on playing at the end-of-season ATP World Tour Finals in London.
Davydenko this week repeated his victories over Federer and Nadal from the 2009 season-ending ATP World Tour Finals in London, where he beat Del Potro in the final.
Swedish ninth seed Robin Soderling kept alive his hopes of snatching a place at the ATP World Tour Finals in London by defeating Croatia's Ivo Karlovic 6-4 7-6.
The World Tour Finals sees the top eight players in the world split into two groups of four, with the top two in each section going through to the semifinals.
In addition to giving tennis a futuristic face-lift, Kermode also believes hosting the World Tour Finals at a venue such as the O2 opens the sport up to a wider audience.
Del Potro is appearing at the ATP World Tour Finals for the first time since 2009, when he lost in the final in the tournament's debut year in the UK capital.
Chile's Fernando Gonzalez, currently in the eighth and final spot in the race to the World Tour Finals, will play Davydenko in the last 16 after beating Brazilian qualifier Thomaz Bellucci 6-3 6-4.
The Russian, who beat the world number one in their last meeting in the last four of the ATP World Tour Finals in London in November, triumphed 6-4 6-4 in one hour and 20 minutes.
Roddick, who has described the tour schedule as "ridiculous" and has yet to qualify for next month's World Tour finals in London, withdrew from his match against Stanislas Wawrinka with a knee injury on Tuesday.
Soderling, who also defeated Nadal at the season-ending ATP World Tour finals in London, had come into the match buoyed by his breakthrough first victory against world No. 1 Roger Federer in the semifinals on Friday.
The 28-year-old is arguably the form player on tour after his success at the ATP World Tour Finals last November and in Doha to start the year -- where he beat both Federer and Rafael Nadal.
Federer, under pressure from Novak Djokovic for the top spot in the rankings, later withdrew from the Paris Masters this week where he is defending champion to rest up ahead of the ATP Tour Finals in London.
Victory for Djokovic was revenge for a defeat to his Davis Cup teammate at the ATP World Tour Finals in London last November and he acknowledged that he was fortunate the match had not gone to a deciding set.
Federer received a warm reception from the 17, 500 fans at the O2 Arena before his ATP Tour Finals victory over Murray and went on to outplay an opponent he had lost against six times in their previous nine meetings.
Djokovic beat the Swiss maestro in the final of the ATP World Tour Finals in London in November as he went back to the top of the global tree, also beating Murray in their round robin group match.
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"I rate the World Tour Finals after Grand Slams as the biggest event in our sport, so being the title defender is a big responsibility, but I don't think I'm the favourite, " he tells BBC Sport after the photo call ends.
Shanghai has made way for London and the Tennis Masters Cup has been rebranded the ATP World Tour Finals, but the principle remains the same - the best eight players in the world battling to end the year as the world champion.
Murray's surprise third-round defeat by Stanislas Wawrinka at Flushing Meadows last month had been followed by a listless display against Ivan Ljubicic in Beijing just nine days ago, but a kind draw in Shanghai helped the Scot work his way back into some form during the early rounds and secure a place at the end-of-season ATP World Tour Finals in London.
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Venus, who has not played on the tour since reaching the semi-finals of the year-end Chase Championships last November, is next scheduled to play on May 1.
Federer - who has yet to win a tour title this year - fell at the quarter-finals in Florida, losing out to Andy Roddick.
She reached the Wimbledon semi-finals that year but has yet to win a regular tour event, and the photogenic Russian's off-court sponsorship deals dwarf the figure she has earned playing tennis.
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