BEIJING – Top seed Jannik Sinner beat Roman Safiullin 3-6, 6-2, 6-3 in the second round of the China Open on Saturday and learned afterwards that his steroid case is far from over.

While Sinner was on trial in Beijing, the World Anti-Doping Agency announced it was seeking a one- to two-year ban for the US Open champion, who tested positive twice for an anabolic steroid in March, but was not suspended by a decision by an independent tribunal announced on August 20 by the International Tennis Integrity Agency because the ITIA found he was not at fault.

Sinner's fate will now be decided by the Switzerland-based Court of Arbitration for Sport after WADA announced on Thursday that it had lodged an appeal.

“Of course I am very disappointed and, to be honest, surprised by this appeal because we had three hearings,” Sinner said at a press conference after his game on Saturday. “All three hearings were very positive for me.

“You know, I wasn’t expecting that. I knew a few days ago that they were going to appeal, that it became official today. But yeah, it’s a surprise.”

On court Saturday, the two-time Grand Slam champion fell behind again in the Chinese capital after Safiullin broke serve twice to secure the first set.

Sinner's power and laser-like accuracy from the baseline gradually gave way to his Russian opponent, helping the Italian win seven games in a row, 2-2 in the second set, securing superiority and a narrow victory.

Sinner, who has reached at least the quarterfinals in every Tour event he has competed in in 2024, will next face Jiri Lehecka, who previously beat Roberto Bautista Agut 3-6, 6-2, 6-1.

Also on Saturday, Italian Flavio Cabolli advanced after a 6-4, 6-2 win over Pavel Kotov.

Third seed Daniil Medvedev played his second-round match against French veteran Adrian Mannarino later on Saturday.

In the women's draw, US Open champion Aryna Sabalenka advanced to the third round with a 6-4, 6-1 win over Thai qualifier Mananchaya Sawangkaew.

“In the first set I had a little trouble with the rhythm,” said Sabalenka, whose best performance in Beijing came in the quarterfinals. “In the second set everything seemed to work much better. I think that’s why it was smoother and better quality.”

Second-placed Sabalenka is the top seed in Beijing in the absence of Iga Swiatek.

Next up for the three-time major winner is American Ashlyn Krueger, who defeated New Zealand's Lulu Sun 6-1, 7-6 (4).

Third seed Italian Jasmine Paolini bounced back from a poor first set to beat Denmark's Clara Tauson 1-6, 7-5, 6-4. Paolini will play Poland's Magda Linette after the 31st seed also needed three sets to defeat Moyuka Uchijima 6-4, 4-6, 6-3.

Ninth seed Daria Kasatkina of Russia defeated Croatia's Jana Fett 6-1, 6-2. She will play Amanda Anisimova, who defeated Camila Osorio of Colombia 1-6, 6-3, 6-4.

Wimbledon champion Barbora Krejcikova lost to Romanian Jaqueline Cristian 1:6, 6:4, 7:5.

Japan Open

Tomas Machac defeated fifth seed Tommy Paul 2-6, 6-3, 7-6 (4) to reach the quarterfinals. This continued a disappointing week for the top seeds in Tokyo.

Top seed Taylor Fritz, third seed Casper Ruud and fourth seed Stefaos Tsitsipas were all beaten in the first round before second seed Hubert Hurkacz was also eliminated as he lost to US Open semi-finalist Jack Draper 6-4, 6-4 in the second round.

Sixth-seeded Holger Rune is the highest-ranked remaining player in the draw. Rune from Denmark defeated home favorite Yoshihito Nishioka 6-2, 6-4.

Defending champion Ben Shelton, the No. 8 seed, is the only other seed still in the quarterfinal draw.

Alex Michelsen of the USA also advanced after a 6-1, 6-4 win over Australia's Christopher O'Connell to set up a quarterfinal match against Machac.

Kei Nishikori defeated Jordan Thompson 6-2, 6-3 and will play Rune in the quarterfinals.