SHANGHAI, China (AFP) — An ailing Novak Djokovic was knocked out of the Shanghai Masters semifinals on Saturday by world No. 204 Valentin Vacherot, who will face his cousin Arthur Rinderknech in a surprise all-family final.

Vacherot, a 26-year-old qualifier from Monaco, beat Djokovic 6-3, 6-4 to deny him a chance at a record-extending fifth title in Shanghai.

He will next face his cousin, the unseeded Rinderknech, who came from a set down to oust Daniil Medvedev 4-6, 6-2, 6-4.

"I'm trying to pinch myself, is this real," said Vacherot after the biggest win of his career.

Vacherot is the lowest-ranked player to reach an ATP Masters 1000 final.

Djokovic, 38, struggled physically throughout the match, throwing up courtside and receiving medical treatment multiple times.

The former world No. 1 said Vacherot's unlikely run in the tournament was "an amazing story." 

"It's all about him," said Djokovic. "The better player won today." 

Djokovic declined to answer questions about his physical state. 

He had said after his last match that he was concerned after battling vomiting bouts, leg injury scares and fatigue throughout the tournament.

However, he looked alert and seemed to be having a dream start when he broke in the first game.

The satisfaction was short-lived as Vacherot broke back instantly.

The Serbian then began having issues in his left leg, stopping to stretch multiple times and dropping to the ground once.

He had to take an extended medical break, lying on his stomach shirtless as a physio attended to his back.

With Djokovic clearly unable to move normally, Vacherot broke again in the eighth game, then fired two aces to hold the ninth and claim the set.

In temperatures of 31C and humidity of 62 percent, Djokovic continued to struggle in the second set but held the first game despite facing breakpoint twice and falling again.

Serving in the ninth game he hit two double-faults in quick succession before recovering, only to ultimately be broken upon committing another.

Despite a last-gasp effort from Djokovic, Vacherot held serve and his nerve to seal victory.