Petr Yan will undergo surgery on a torn ACL on Tuesday, the former UFC bantamweight champion announced on social media.
Yan (17-5) revealed multiple injuries in a post on X.
"MRI confirmed ACL rupture, meniscus tear and groin injury," Yan wrote. "Surgery is scheduled for [Tuesday]. Nothing will break me, I'm determined to come back stronger than ever in no time."
Daniel Rubenstein, Yan's manager, told ESPN on Tuesday that his fighter tore his ACL during the first round of his March 9 win over Song Yadong at UFC 299.
Yan faces a 9-12 month recovery following surgery, Rubenstein added.
Yan was in desperate need of a win against Yadong, having lost three in a row during a 13-month stretch over 2022 and 2023. The 31-year old Russian won the UFC title in 2020 with a victory over Jose Aldo, but lost the belt immediately via disqualification in a title defense against Aljamain Sterling.
Yadong (21-7-1) was considered one of the UFC's top rising title contenders going into UFC 299. The loss to Yan dropped his UFC record to 10-3-1.