Novak Djokovic eventually tamed Danish debutant Holger Rune with a 7-6(4) 6-7(1) 6-3 victory in his opening round robin match at the ATP Finals to seal the year-end number one ranking for a record-extending eighth time.
The 36-year-old Serb was stretched to the limit at times with Rune producing some fireworks for the large evening crowd in Turin’s cavernous Pala Alpitour.
But after an uncharacteristically poor second-set tiebreak, Djokovic made his experience count as he began his quest for a record seventh title at the year-ender.
Earlier on day one, Jannik Sinner made a dream start in front of his home crowd with a 6-4 6-4 defeat of Stefanos Tsitsipas in their opening Green Group clash.
Djokovic will next face Sinner on Tuesday.
The Serbian’s 19th successive win ended any chance of Spain’s Carlos Alcaraz overtaking him in the rankings this week.
A sensational first set had the crowd on the edge of their seats with Djokovic edging it on the tiebreak.
But the 20-year-old Rune, who had won in two of their first four meetings, was undeterred and cranked up the power to take the set to another tiebreak which he raced away with.