LONDON – Alexander Zverev set up a last-four clash against Roger Federer in the ATP Finals after seeing off John Isner 7-6 (7/5) 6-3 on Friday, while Novak Djokovic will take on Kevin Anderson.
Zverev played American giant John Isner at London's O2 Arena knowing a win by any scoreline would take him through to the semi-finals of the season-ending tournament.
The turning point in the round-robin match came at the end of the 12th game, when the 21-year-old German saved a set point on his own serve with an ace, going on to force a tie-break.
The players swapped mini breaks, but the giant Isner then faltered again on his own serve to hand the set to Zverev – meaning he no longer had any chance to qualify for the last four.
In the second set a single break of serve in the eighth game proved decisive as Zverev served out the match.