World No.118 Alina Charaeva produced the biggest upset of the China Open on Saturday, beating new world No.1 Elena Rybakina 3-6, 6-4, 6-3 in Beijing.

The 24-year-old Armenian rallied from a set down in a two-hour, 11-minute battle. She is the lowest-ranked player since rankings began in 1975 to come from a set behind and beat the world No.1. Rybakina is only the second player, after Naomi Osaka in 2019, to lose her first match as world No.1.

Charaeva won 76 per cent of points behind her first serve and converted five of eight break points. Rybakina, playing her first match since winning the US Open, struggled with seven double faults. It was Charaeva’s first career match against a top-20 player.

“I don’t have words to say. I’m out of words. This is incredible,” Charaeva said on court. The Russian-born Armenian said she tried to stay mentally strong even after dropping the opening set against the three-time Grand Slam champion.

Charaeva will face Britain’s Sonay Kartal in the third round. In the men’s draw, top seed Zverev cruised past Shang Juncheng 6-0, 6-3 to set up a Sunday quarter-final against six-time champion Djokovic.