In the opening of Avengers: Infinity War, Hulk takes on Thanos and it does not go well for Hulk. He’s beaten handily by the Mad Titan, and it’s a bit of a surprise since Hulk is kind of undefeated everywhere he goes. Furthermore, in the comics, he’s arguably one of the most powerful superheroes because hurting him only makes him angrier, which in turn makes him stronger. If you try to defeat Hulk through brute force, you’ll lose because he just gets bigger and more powerful.

But if Hulk had been able to take down Thanos in the first ten minutes, people probably would have asked for their money back. At Collider’s exclusive Q&A screening of Infinity War with the film’s directors, Joe and Anthony Russo, they gave their reasoning for how Thanos was able to take down the big green guy:

“I would say that he’s just that powerful. You didn’t see him actively use the power stone in that fight. I think ultimately, the way we looked at that fight and the way talked about it with our stunt team when we were executing it was Hulk is obviously very powerful, but he’s a little mindless in his fighting style. It’s aggressive, it’s pummeling. Thanos is the Ghengis Kahn of the universe, he’s a very skilled fighter, equally as strong. So when you put those two up against each other, the more skilled fighter is going to win ultimately. Which is why Hulk has a moment where he overpowers Thanos, but ultimately Thanos is smart.”

It’s not the most satisfying explanation—all you need to defeat Hulk is to be a better fighter than him—but it’s what the movie required. Also, it’s important to establish to the audience that Thanos isn’t going to be taken down in a mano-a-mano fight. Keep in mind, that until this point, Thanos has come off as fairly ineffective, so everything has to build to making him seem as threatening as possible, and defeating the Hulk without breaking a sweat accomplishes that even if it might not sit comfortably with Hulk fans in the audience.

Watch the Russos give their answer in the video above, and for more from our Q&A with the Russos, click on the links below: