Dwayne “The Rock” Johnson delivers what a Toronto critic called his most nuanced and vulnerable performance to date as two-time early UFC heavyweight champion Mark Kerr in Benny Safdie’s biographical drama "The Smashing Machine," which screened Monday at the Toronto International Film Festival and opens in theaters Oct. 3.

The 123-minute film trades conventional sports-movie climaxes for a quieter character study of Kerr’s rise and struggles between 1997 and 2000. While Johnson’s work drew immediate praise for its restraint and emotional clarity, the movie’s measured pacing and subdued fight sequences prompted mixed reaction from the reviewer, who said the film often feels sleepy and that the restrained approach can blunt audience involvement.

Director Benny Safdie, who co-directed "Uncut Gems" with his brother Josh, purposefully resists many of the genre’s tropes. Rather than scoring contests with triumphant anthems, Safdie overlays some fight moments with jazz, and he frames the early MMA world in a grainy VHS aesthetic that emphasizes grit over glamour. The reviewer noted that many fights are short and understated — sometimes 30 seconds to a minute — and that key episodes, including Kerr’s overdose and his stint in rehab, occur offscreen.

Emily Blunt plays Dawn, Kerr’s on-again, off-again girlfriend, and the reviewer said the pair’s chemistry is well-honed from prior collaborations, though Dawn’s storyline is described as underdeveloped. Former MMA fighter Ryan Bader, portraying Mark Coleman, is singled out for providing a particularly documentary-real emotional center in scenes with Johnson’s hospitalized Kerr.

Safdie’s attention to period detail is evident in the film’s settings: unglamorous international fight circuits, green-hued locker-room showers, and the general look of an era before the sport’s mainstream commercialization. Those design choices, the critic wrote, allow Johnson to disappear into the role in ways that earlier action-oriented projects did not.

The review framed Johnson’s turn as a career moment that chips away at his larger-than-life persona, suggesting it could open doors to more dramatic projects, while also noting that the film itself may be too subdued to serve as a broad launchpad. The movie’s stylistic choices — traded spectacle for intimacy, conventional climaxes for quiet character beats — will likely determine whether audiences and awards voters respond in equal measure.

"The Smashing Machine" arrives in theaters Oct. 3. The film’s TIFF screening and critical responses position it as a notable entry in Johnson’s evolving filmography, underscoring a performance that some say is the actor’s most serious to date even as the film’s tone and pacing divide opinion.

Dwayne Johnson with Emily Blunt in 'The Smashing Machine'