Novak Djokovic stayed on track for a record-breaking seventh Association of Tennis Professionals Finals title after Italy's Jannik Sinner beat Holger Rune 6-2, 5-7, 6-4 Thursday to seal the Serbian world No 1’s semi-final ticket.
Sinner was already guaranteed a spot in the last four after Hubert Hurkacz claimed a set in his 7-6 (7/1), 4-6, 6-1 defeat to Djokovic earlier in the day, and the world No 4 topped the group after a battling win at Pala Alpitour in Turin.
"It was hard, I'd never beaten him before...the crowd helped me a lot," said Sinner.
"I'm pleased with how I won the game." With Sinner already assured of a semi-final berth, the Italian could have lost against Rune knowing that a defeat would eliminate Djokovic from the tournament.
But Sinner fought hard to secure first place with his third win in three group matches, allowing world No 1 Djokovic to follow him into the next round. In the semis the reigning Toronto Masters champion will play whoever finishes second in the Red Group, while Djokovic will face the group winner.
Carlos Alcaraz and current Red Group leader Daniil Medvedev - who is also already in the semis - face off Friday afternoon before Alexander Zverev takes on eliminated Andrey Rublev.
Sinner initially looked like making short work of Rune despite the Dane only having to play three games in his previous match with Stefanos Tsitsipas Tuesday before the Greek dropped out of the tournament injured.