UFC heavyweight champion Francis Ngannou will require surgery to repair MCL and ACL injuries, his manager has confirmed.

Ngannou retained his heavyweight title with a unanimous decision victory over Ciryl Gane in Anaheim on Saturday.

The 35-year-old got the better of his former training partner Gane for the first victory by decision of his 17-3-0 UFC career.

Ngannou then revealed he had actually torn his MCL and damaged his ACL while sparring in preparation for the fight.

His manager, Marquel Martin, told ESPN on Wednesday that Ngannou will spend some time resting back home in his native Cameroon and that the "plan" is to have surgery once he returns to the United States.

It is estimated Ngannou will be out for nine months recovering from the injuries.

"I continue to be amazed and inspired by Francis' heart and resilience," Martin said.

"Fighting on one leg to overcome all odds and remind the world he is the undisputed heavyweight champion of the world. I think we can all agree he deserves some time to go back home and be with his family and countrymen.

"Upon his return, we plan on getting surgery and starting the recovery process so we can get him back to 100 percent as soon as possible.

"In the meantime, we hope we can find a peaceful resolution in these contract talks [with the UFC]. We'd like to thank all the fans for their continued support and belief in Francis."