SHANGHAI, China (AFP) — Grigor Dimitrov fought back to beat top seed Carlos Alcaraz in three sets and reach the quarterfinals in the latest upset at the Shanghai Masters.

The 18th seed won 5-7, 6-2, 6-4 against an out-of-sorts Alcaraz as the Bulgarian steps up his pursuit of a first ATP title since 2017.

He will next face the 22nd-seeded Nicolas Jarry after the Chilean defeated wildcard Diego Schwartzman 6-3, 5-7, 6-3.

The first Shanghai Masters since the pandemic has opened up for Dimitrov after the exits of Daniil Medvedev, Stefanos Tsitsipas, Holger Rune and Jannik Sinner.

Russia's Andrey Rublev is the highest remaining seed left in the draw at five.

World No. 1 Novak Djokovic is not in China.

"I'm still here, I'm not going anywhere," the 32-year-old Dimitrov said after dismissing Alcaraz.

Spain's Alcaraz, the world No. 2, was chasing a seventh tour-level title of the season but he uncharacteristically crumbled after winning the first set.

The 20-year-old Alcaraz took time to find his range and Dimitrov broke for 3-2 in the first set with a vicious whipped forehand return.

Dimitrov was broken back as he served for the set in a riveting 10th game involving two thrilling rallies that both times saw Alcaraz come out on top.

Alcaraz held and then broke again to wrap the set up in just under an hour.

But rather than power on to victory, Alcaraz let the match get away from him.

The clean-hitting Dimitrov gathered himself to race into a 2-0 lead in the second set, then broke again for 5-2, before sealing the set when Alcaraz shanked his return.

They went to a decider and an unusually flustered Alcaraz was broken in the third game after yet another unforced error.