DOMINIC THIEM produced one of the best performances the O2 Arena has seen since it started hosting the ATP Finals in 2009 to stun Novak Djokovic.
The Austrian fell a set behind but turned on the heat and played lights-out tennis to claim a 6-7 6-3 7-6 victory and book his place in the last four for the first time.
It means Djokovic and Roger Federer will now face off in a showdown battle on Thursday with the winner joining Thiem in Saturday’s semis.
The Swiss ace earlier saw off Matteo Berrettini 7-6 6-3, with the Italian No8 seed now unable to progress out of the group.
- Thiem fights back from a set down and 4-1 in the deciding tie-break to beat Djokovic and advance
- Federer beats Berrettini in straight sets at the O2 Arena in London
- Watch Djokovic vs Thiem on Amazon Prime