Rybakina, who lost to world number 118 Alina Charaeva in Beijing, said she would take time away from competition to recover.
"I'm very sorry to the fans who were looking forward to seeing me play," Rybakina said in an Instagram story shared by the tournament.
"I'll take some time to rest and recover. Thank you for your understanding and continued support."
The 27-year-old has been managing a lingering lower leg and foot problem that also forced her to retire from her Cincinnati quarter-final against Iga Swiatek in August.
Despite the setback, Rybakina recovered in time for the US Open, where she claimed her third Grand Slam title, rose to world number one and became the first player to qualify for the season-ending WTA Finals.
Rybakina is next expected to compete in Ningbo, where she will attempt to defend her title.
The Wuhan Open is scheduled to take place from October 12th to 18th.