San Francisco Frontiers - Medvedev to face De Minaur in Shanghai quarter-finals

There he will meet world number seven Alex de Minaur, who cruised past Portugal's Nuno Borges 7-5, 6-2 earlier in the day.

Victory in Shanghai comes over a week after the 36th-ranked Tien took the Russian out of the China Open semi-finals in Beijing.

"He's an unbelievable tennis player," Medvedev said. "Outside of the big three, he may be the toughest opponent I've ever faced."

Medvedev broke first in the ninth game, but Tien returned the favour immediately.

The last two games of the first set saw the two players locked in an epic back-and-forth, their prolonged rallies thrilling the crowd.

Both faced breakpoint but managed to hold, with Medvedev smashing a looping lob from Tien to send them to a gripping tiebreak.

Medvedev broke early in the second set, but Tien was again unphased –- breaking back in the fifth and then seventh games, before the former world number one levelled again in the tenth.

Medvedev began limping just before the second-set tiebreak and spoke briefly with a medic before hobbling back onto court.

Tien went 3-0 up as the Russian, ten years his senior, tried to stretch out on court, becoming increasingly irate as the match was pushed to a decider.

A scrappy third set full of double-faults from both players was decided when Medvedev broke in the ninth game with a backhand.

- 'Going to be a battle' -

His next opponent De Minaur is, after Novak Djokovic, the highest ranked player left standing in the tournament after a string of high-profile exits.

The first set heated up when the Australian needed five break points in the 11th game against Borges, converting the last with a backhand for a decisive advantage.

De Minaur carried the momentum into the second set, breaking in the first and third games.

He remained cautious about his title chances, despite the elimination of so many top seeds, including second- and third-ranked Jannik Sinner and Alexander Zverev.

"In our side of the draw, there's a lot of quality players, so it's still going to be a battle," he said.

Another top-10 player fell on Wednesday as Italy's Lorenzo Musetti lost to Canada's Felix Auger-Aliassime 6-4, 6-2.

Thirteenth-ranked Auger-Aliassime looked sharp throughout, breaking in the fifth game.

He went on to dominate the second set, breaking Musetti, the world number nine, in the fifth and seventh games.

"I knew it was going to be the toughest match of the week so far, and I knew I was going to have to raise my level, and I did," said the 25-year-old Canadian.

He will next meet France's Arthur Rinderknech, who reached his first Masters 1000 quarter-final after beating Czech Jiri Lehecka 6-3, 7-6 (7/5).

Rinderknech's cousin Valentin Vacherot made it to the last eight on Tuesday, and will face Denmark's Holger Rune for a place in the semi-finals.

Djokovic will follow them on to court on Thursday against Belgium's Zizou Bergs for a place in the last four.

X.Roberts--SFF