Claudio Castagnoli was set to sign a long-term agreement with All Elite Wrestling prior to Forbidden Door, where he debuted as Zack Sabre Jr.'s mystery opponent.
This is according to Fightful Select. At the time of publishing, the outlet wasn't able to confirm whether or not the contract had actually been signed.
Fightful note that AEW had prepared promotional materials and merchandise for Castagnoli prior to his arrival, with the former WWE star spotted backstage during the course of the evening.
It is also stated that serving as Sabre Jr.'s mystery opponent wasn't AEW's original plan for Claudio's debut, though there's currently no word on what the company had in mind instead. Bryan Danielson was originally pegged to face Zack at Forbidden Door but was forced to pull out due to injury prior to the event.
The former Cesaro defeated ZDJ and was made Forbidden Door's centrepiece by the end of the night, helping the Blackpool Combat Club, Eddie Kingston, Santana, and Ortiz clear the ring of the Jericho Appreciation Society, swinging Angelo Parker dozens of times in the process. Claudio now joins his new allies in AEW's second Blood and Guts match on Wednesday's Dynamite.