"They used a stand-in for Josh," said Benedict Cumberbatch, who plays Doctor Strange in the MCU, told Radio Times. "Josh wasn't in there for much, he did his bit and then a lot of stuff with a lot of us and him was missing because, I guess, he was doing Deadpool 2 and I was doing Melrose and The Current War." (Brolin plays Cable in the Deadpool sequel.)
After Cumberbatch revealed Doctor Strange will get into "more trouble" in Infinity War, he starts talking about Brolin at the 38-second mark.
"But we made it work," continued Cumberbatch. "It’s often the case you can act with other actors anyways, in certain scenarios, because of the amount of additional stuff you have to fit in with the environment or the magic or whatever it is that’s coming out of your hands or your ass."
He added that Infinity War does look like they were all there together, though. "I don't feel robbed of the opportunity. There's plenty of footage showing there's definitely all of us there," he said.
As for the looming character deaths in Infinity War, Cumberbatch said Doctor Strange "might not make it out of the film alive" since he's not contractually obligated to appear in any further films.
There's only one way to find out. Avengers: Infinity War arrives in theaters April 27, three weeks before Deadpool 2 lands on May 18. In the meantime, a Deadpool pop-up bar will arrive in New York and Los Angeles.