Rezar was in an eight-man match with Seth Rollins, Murphy, and AOP partner Akam against the Street Profits and Viking Raiders and during the match, Montez Ford hit Rezar with a crossbody which is where the tear occurred.
He continued to work the rest of the match with one arm as his right arm dangled, something Bryan Alvarez noted on the post-Raw Wrestling Observer Radio, leading him to speculate the biceps was torn.
As of this writing, WWE has yet to formally announce the injury. Meltzer assumed Rezar would be taken off TV as he recovers, speculating he could be out 6-to-8 months if he needs surgery and several months if he doesn't.
The 25-year-old born Gzim Selmani signed with WWE in 2015 and spent four years in NXT with Akam (Sunny Dhinsa) before getting called up to the main roster in 2018. The team missed a chunk of time in 2019 when Akam was recovering from a leg injury.