The 20-year-old Italian, who is 13-ranked in the world, had a tough match against the Swede.
After a loss in both the first and second sets, Ymer woke up. The third set was even, but the Swede eventually pulled the longer straw. In the fourth set, the energy tired for Ymer, who with a third set loss also lost the match.
Sinner’s victory numbers were written 3–1 (6–4, 6–3, 5–7, 6–2).
The match lasted for three hours and three minutes
In the third round of the tournament, Sinner will face the winner in the meeting between Andy Murray, from Great Britain, and the American John Isner.