According to Rockhold, his surgically repaired left shin recently got infected again, forcing him to have a stem-cell graft inserted. In addition, he said he sprained his right knee on Thursday and also recently broke his nose.
"I need at least one weapon to make it to the party," he said.
Rockhold is hoping to return to action in late 2018 or early 2019 after what his doctors are saying will be a four-week recovery.
The UFC will keep Weidman on the Nov. 3 card at Madison Square Garden in New York. Ronaldo "Jacare" Souza will take the place of Rockhold.
Rockhold-Weidman 2 was a rematch of a fight that happened at UFC 194. Rockhold won via fourth-round TKO en route to becoming middleweight champion.