Grand Slam record winner Roger Federer also won his final third group game at the ATP Final.
The Swiss player, who had previously been a semi-finalist, went through the 6:7 (5:7), 6:4,6:1 against Marin Cilic from Croatia (No. 5) in 1:55 hours without being forced into the final round of London.
“It was a difficult match, I was a little indecisive on some points. But it’s nice to play without the usual pressure,”he said.
On Thursday evening, the two tournament debutants Alexander Zverev (Hamburg/No. 3) and Jack Sock from the USA (No. 8) played the second semi-finalist of the Boris-Becker Group in a direct duel. Former US Open Champion Cilic had no chance of advancing even before the match against reigning Australian Open and Wimbledon winner Federer.
The 36-year-old Federer has already won this year’s $8 million season-end tournament six times – most recently in 2011.
In the parallel group, Grigor Dimitrov has already been appointed semi-finalist and relay winner. On Friday the Austrian Dominic Thiem (No. 4) and David Goffin from Belgium (No. 7) will play for the last free place in the semifinals.
Cincinnati winner Dimitrow will face Pablo Carreno Busta, who stepped in as a replacement after the injury-related retreat of his Spanish compatriot Rafael Nadal (No. 1).