(Photo credit: Mike Frey-Imagn Images)

Jannik Sinner began his title defense at the Rolex Shanghai Masters with a win, defeating Daniel Altmaier of Germany 6-3, 6-3 on Saturday in the ATP Masters 1000 event.

Sinner, the World No. 2, is trying to become the first player since Novak Djokovic (2012-13) to win back-to-back titles in Shanghai. He won the ATP 500 China Open in Beijing earlier this week.

It took one hour, 38 minutes for the Italian to defeat Altmaier, who defeated him in their most recent meeting in 2023 at the French Open.

'I knew before the match it was going to be very difficult today,' Sinner said. 'I didn't have a lot of time to adapt here, but it makes it even more special. Every day, every opponent is very difficult, it's a huge challenge. So I'm very happy to come through today and hopefully I'm able to raise my level tomorrow.'

Sinner is accustomed to playing at a high level in China, where has a 23-2 career record and three titles, having also won in Beijing in 2023.

And he was efficient against Altmaier, winning points on 88 percent (30 of 34) of his first serves, compared to 63 percent (22 of 35) for his opponent. Sinner converted three of four break chances.

In the third round -- Sinner had a first-round bye -- he will meet Tallon Griekspoor of the Netherlands, the No. 27 seed.

No. 3 Alexander Zverev of Germany topped Valentin Royer of France 6-4, 6-4 but injured his right toe as he served for the win at 5-4.

'I don't know, I landed funny on my toe and after that I could barely do a step, so we'll see what it is,' Zverev said. 'Not happy to end the match like that, of course, but I think definitely happy with the level in the first round of a Masters. That was quite good. He is playing very well and moving forward, we will see if I will ever be healthy this year again, because it's been a struggle. But I'm happy to be through.'

Alex de Minaur, the No. 7 seed, eliminated Camilo Ugo Carabelli of Argentina 6-4, 6-2 in just 88 minutes. It was his 48th win of the season, most by an Australian man since Lleyton Hewitt in 2004.

'I'm happy with myself. It's a great achievement to show the consistency,' de Minaur said. 'I feel like I probably could have broken that record last year if I hadn't gotten injured. To come back this year and just show that consistency week-in and week-out, I'm very proud of my efforts. Saying that, there's still a lot of tennis to be played, so hopefully I can keep adding wins to that tally.'

No. 9 seed Karen Khachanov of Russia fell to Juncheng Shang of China, who emerged with a 7-6 (3), 6-3 win.

Another Russian, Daniil Medvedev -- once the World No. 1 who is working to rebuild his game after a down season that saw him win just one match in the four Grand Slam events -- also moved on. The No. 16 seed, he ousted Czech qualifier Dalibor Svrcina 6-1, 6-1 in just an hour. His next opponent will be No. 18 seed Alejandro Davidovich Fokina of Spain, who defeated Italy's Matteo Arnaldi 6-4, 6-4.

Also advancing to the third round were Lorenzo Musetti (No. 8) of Italy, Canadians Felix Auger-Aliassime (No. 12) and Denis Shapovalov (No. 23), Kamil Majchrzak of Poland, Czech Jiri Lehecka (No. 15), Yoshihito Nishioka of Japan, Arthur Rinderknech of France, American Learner Tien and Jesper De Jong of the Netherlands.

--Field Level Media