World no 1 is not my goal: Rafael Nadal
Nadal came to London as current world No 1 but needs to win more matches for ending this season in the top position, as Serbian Djokovic is only 640 points behind him.
Nadal came to London as current world No 1 but needs to win more matches for ending this season in the top position, as Serbian Djokovic is only 640 points behind him.
Alexander Zverev or Jack Sock will advance with Roger Federer as the second qualifier from the Becker group.
"I'm extremely happy... It's been a tough group so to be there in two matches is great," Federer said.
The 25-year-old beat fifth seed Marin Cilic 5-7, 6-2, 7-6 (4) to move to 1-1 in Group Boris Becker.
The 26-year-old Bulgarian broke his Austrian rival three times to win the match.
Rafael Nadal and Roger Federer can set up a dream climax to the 2017 season at the ATP World Tour Finals.
Federer's decision paved the way for Nadal to end the year as World No.1 for first time since 2013.
Andy Murray beat four-time defending champion Novak Djokovic in straight sets at London's O2 Arena on Sunday to win the…
Murray took just 86 minutes to defeat the Swiss number one 6-4, 6-2.
However, the top-ranked Scotsman has not yet qualified for the semifinals at tennis' eight-man, year-end championship.
