UFC flyweight champion Demetrious Johnson had successful shoulder surgery on Wednesday, according to a report by Ariel Helwani of MMAFighting.com.  A timetable for his return to action is unknown.

Johnson last fought on October 7th of 2017, where he broke Anderson Silva’s promotional record for consecutive title defenses, successfully retaining his belt for the 11th straight time with a highlight reel submission victory over Ray Borg at UFC 216.

The 31-year-old is the only fighter in UFC history to hold the flyweight belt and has not lost an MMA fight since 2011.