The Upper West Side deli where I meet Benny Safdie is filled with a particular kind of grumpy old-school Manhattanite. They’re the type of figure who has tended to populate the filmmaker’s movies: many of them neurotic, and more concerned with finding a means to their own ends than placating the people around them. With his brother, Josh, Benny has built a career on his fascination with these occasionally surly characters, often men on the downswing. For his first solo directing effort, The Smashing Machine, Safdie focuses on a somewhat unexpected figure: a sports champion, albeit one who is learning what it’s like to fail. “I want to know what it feels like to go through that,” he told me, over a plate of eggs, discussing the film. It’s an uncomfortable portrait—of who the winner becomes when he starts to lose.

Safdie has zeroed in on one athlete in particular: the mixed-martial artist Mark Kerr, played here by Dwayne “The Rock” Johnson. Kerr—an absolute wall of a man, and thus a role befitting of Johnson—became renowned for his unassailable winning streak throughout the late ’90s and early aughts. The film’s basic plot resembles that of many traditional sports biopics. It follows the height of Kerr’s career, as well as his eventual battle with a painkiller addiction and his rocky relationship with his girlfriend, Dawn (played by Emily Blu