Grigor Dimitrov takes down Carlos Alcaraz in Shanghai - ESPN

SHANGHAI -- Grigor Dimitrov upset second-ranked Carlos Alcaraz 5-7, 6-2, 6-4 to reach the quarterfinals at the Shanghai Masters on Wednesday.

Dimitrov, who hadn't beaten the former world No. 1 in their three previous meetings, was crisp from both wings and used his backhand drop shot to keep Alcaraz off balance. The Bulgarian struck 29 winners and 10 aces and rallied after relinquishing a 5-3 lead in the first set to reach his 17th Masters quarterfinal.

"I stayed in the match, that was the first thing, especially after the first set," Dimitrov said. "After the second break in the second set, I think I understood his service games and was able to put more balls in and read his serve a bit better.

"I think in the third set it was a bit of cat-and-mouse. I think we both played a solid set. He made a few errors, and I was very solid and served well when I had to."

Dimitrov will next meet 22nd-seeded Nicolas Jarry, who beat wild-card Diego Schwartzman 6-3, 5-7, 6-3 to make the final eight of a Masters tournament for the first time.

Also, Ugo Humbert eliminated J.J. Wolf 6-1, 6-2 in a dominant 58-minute victory. The 32nd-seeded Frenchman did not face a break point and had 17 winners to Wolf's four.

"It was a great performance from me. I played a great level," Humbert said. "I'm very proud. I was really focused from the beginning until the end. Last year I was in Challengers, so it's a great improvement. It's daily work, and we built something good. I'm very happy to be in the quarters here."

Humbert will play fifth-seeded Andrey Rublev, who beat 12th-seeded Tommy Paul 7-5, 7-5.