World number one Jannik Sinner overtook Alex de Minaur after Taylor Fritz beat an angry Daniil Medvedev on the opening day of the ATP Finals.
Sinner, playing at home in Turin, Italy, won 6-3 6-4 to extend his perfect record against seventh seed Australia.
Earlier, American Fritz recorded his 50th victory of the year by beating Medvedev 6-4 6-3 as the group stage of the season-ending tournament began.
“I’m super happy with the way I played today,” said Fritz, who reached his first Grand Slam final at the US Open in September.
Fourth-seeded Medvedev committed seven double faults in a tight first set in the Ilie Nastase group, including two in a row to give Fritz a set point.
Closing out a calamitous service game, the Russian double-faulted again and reacted angrily to being behind by smashing his racket against his seat and the floor.
At the start of the second set, Medvedev got his first break point of the match but slammed his backhand return into the net.
Further break points went unconverted for both players before fifth seed Fritz, 27, took advantage of his third, with a missed lob that landed on the baseline.
An irritated Medvedev then received a penalty point after breaking a microphone on court by throwing his racket.
As his behavior deteriorated, he was booed by the crowd for his antics, including holding his racket by his head while waiting to receive a serve.
“I’m angry, frustrated. This time, completely at myself, not at anyone. Just at myself,” Medvedev, 28, said.
Fritz easily served out the match but said that, despite his opponent’s behavior, he could not rest until the victory was confirmed.
“It’s very easy sometimes when someone does this to relax and think they’re going to get it over with, and then you lower your level,” he said.
“I had to stay focused and play a good match, because he was going to fight. I served a good match.”
Winning start for Sinner at home
Sinner finished runner-up to Novak Djokovic at last year’s ATP Finals and has dominated this season, winning his first two Grand Slams – at the Australian and US Opens – among the Tour’s leading seven titles in 2024, all in the middle of a ongoing doping controversy.
The 23-year-old had not played for four weeks since his victory in Shanghai and got off to a slow start against De Minaur, who took advantage by breaking the first as the Italian played a backhand out of bounds.
But De Minaur – who was making his tournament debut – was reminded of the challenge ahead when Sinner immediately nullified his advantage, confirming it with two love holds and a break of his own.
After serving the first set, Sinner controlled the second, breaking in the fifth game after two more holds to love. He had raced to 0-40 on his opponent’s serve, but after a brief pause while a sick spectator was treated, De Minaur stemmed the flow of points by bringing the game to deuce, only for Sinner to break on the fourth occasion.
He wasted no time in wrapping up the victory, shooting a flawless match with his eighth ace of the evening.
Sinner now holds an 8-0 record against the 25-year-old De Minaur, who has won just one set in all meetings.
“I’m very happy,” Sinner said. “I started with a few unforced errors, he was playing really well at the start of the match. I just tried to stay there mentally knowing that at some point my tennis would come. It came quite early then and I started to come back very well.
“I am very happy with this victory and I hope it will give me confidence for the next one.”
On Monday, the John Newcombe Group players kick off their campaign as Spaniard Carlos Alcaraz takes on Norwegian Casper Ruud from 1:00 p.m. GMT, before Germany’s Alexander Zverev – two-time ATP Finals champion – takes on the Russian Andrey Rublev during the evening session. .
In doubles, Great Britain’s Henry Patten and his Finnish partner Harri Heliovaara began their tournament with a 7-6 (7-2) 6-4 victory over second seeds Marcel Granollers of Spain and Horacio Zeballos of Argentina.