BEIJING (AFP) -- Jannik Sinner said holding his nerve in "important moments" was the key to edging out world number three Daniil Medvedev in Wednesday's China Open men's final, which turned on a pair of high-stakes tie-breaks in Beijing.

The Italian triumphed 7-6 (7/2), 7-6 (7/2) in an otherwise deadlocked match to claim the first such tournament since 2019 after Beijing ditched tight pandemic-era health restrictions.

Neither man was able to break the other's serve but Sinner missed a presentable opportunity in the first set when he walloped an overhead volley long on break point and allowed the Russian to hold from deuce.

It was a different story in the tie-break, with the world number seven racing into a 5-0 lead and sealing the deal when Medvedev struck a forehand into the net.

A similar stalemate ensued in set two with the first dozen games going with serve before Sinner again showed his composure when it mattered.

He took the lead in the tie-break with a deft drop shot and never looked back, whipping a stunning cross-court passing shot for match point and battering back a Medvedev serve to seize victory in front of a raucous crowd.

"At some point, I started to return a little bit better... read his serve a little bit better, and that gave me confidence, especially for the tie-break," Sinner said at a post-match news conference.

"The important moments in every match... today I also managed somehow that they (went) my way," the 22-year-old added.

"Today's final was a very high-level final, (and) I'm very happy about the ending of this tournament," he said.

Medvedev admitted that his opponent played "much better than me" in both tie-breaks.

"He managed to control his emotions better in these tie-breaks (and) not make mistakes... (while) I made some easy ones," said the 27-year-old.

"In a way it's luck, but also experience and stuff like this. That's why he won."

World number two and tournament favorite Carlos Alcaraz was eliminated by Sinner in their semifinal on Tuesday.

The top-ranked men's player, Novak Djokovic, is not playing in China this year.

Swiatek into quarterfinals

Earlier, world number two Iga Swiatek swatted aside compatriot Magda Linette to surge into the China Open quartersfinals with a 6-1, 6-1 victory.

Swiatek raced into a 5-0 lead in the first set and snuffed out any hope of an unlikely comeback when she forced her fellow Pole to fire a forehand long.

The four-time Grand Slam champion then presided over a second-set masterclass, blitzing an exhausted Linette with an unrelenting salvo of mighty groundstrokes to wrap up the match in just over an hour.

Swiatek faces Ukraine's Anhelina Kalinina or the ninth seed Caroline Garcia of France next.

"It's always nice to play like that because you make your opponent run," Swiatek said after the match.

"But overall, I just kind of played what I felt I needed to and what I felt was right at the moment."

World number four Jessica Pegula crashed out with a 6-4, 6-2 defeat to Latvia's Jelena Ostapenko.

Ostapenko faces Liudmila Samsonova in the last eight after the Russian defeated Ukraine's Marta Kostyuk 6-4, 6-7 (4/7), 7-5.

Murray misery deepens in Shanghai

Meanwhile, the first round of the ATP Shanghai Masters kicked off in the financial hub Wednesday.

A delighted home crowd watched on as Zhang Zhizhen and Bu Yunchaokete both made it through to the second round -- the first time two Chinese men have done so.

Serbia's Dusan Lajovic eliminated three-time major champion Stan Wawrinka in straight sets to add to his impressive list of wins this year -- including over Djokovic and Sinner.

But Britain's Andy Murray had a miserable night, losing to Russian Roman Safiullin 6-3, 6-2.

The loss crowns a disappointing set of recent results for the 36-year-old, who has won the tournament in Shanghai three times previously.

He also crashed out of the China Open in the first round last week in Beijing.