In Rod Serling’s “Requiem for a Heavyweight,” a teleplay remade for the big screen in 1962, an over-the-hill prizefighter was persuaded by his sleazy manager to humiliate himself by becoming a pro wrestler. Darren Aronofsky’s film takes things one step further: here an aging grappler suffers a heart attack and must try to cope with forced retirement. And as if to blur the distinction between art and life, the wrestler’s played by Mickey Rourke, who once retired from acting for a career as a boxer. It’s a pretty dizzying blend.

But that’s not an adjective that will be applied to the style of “The Wrestler,” a film that’s as straightforward and unfussy as its title. As such it’s a distinct change of pace for Aronofsky, who filled the screen with dazzling effects in his low-budget debut “Pi” as well as the follow-up “Requiem for a Dream,” and then blew things wide open in his flamboyantly incoherent “The Fountain.” His work here, however, is direct and unpretentious—words that could never be used about his previous pictures. It’s an approach that’s well suited to Robert Siegel’s script, especially at the points when it veers into territory that could have become mawkish in other hands.

So too is the performance of Mickey Rourke as Randy “The Ram” Robinson, the fifty-year old who was once a draw at major wrestling contests but has been reduced to eking out a living in tiny small-town venues where he gets a share of whatever the take is from ticket sales. It’s a hand-to-mouth existence that he has to supplement with income from a job in a supermarket stockroom, and even then it’s a close thing: as we meet Randy, he’s been locked out of his dumpy trailer home at a New Jersey lot due to non-payment of rent.

But Randy still has the camaraderie of the fly-by-night wrestling business, and that keeps him going. Some of the best moments in the picture are those that show him and the other, younger grapplers preparing the choreography of their matches and taking care of one another, bloodied and bruised, afterward (or appearing together at sparsely-attended mini-conventions for fans). The actual matches are authentically ludicrous and genuinely brutal. But these wrestling sequences are matched by those that show Randy at his grocery gig, especially after he has to beg his snarky boss for some overtime, which leads to a stint at the deli counter that has tragicomic features.

The overtime’s needed because Randy suffers a heart attack after a match and has to give up the work he obviously cherishes. That leads him to try to get closer—emotionally, that is—to his sole female acquaintance, an aging stripper named Cassidy (Marisa Tomei) who turns out to be a single mom with higher aspirations, and to rebuild bridges with his long-estranged daughter Stephanie (Evan Rachel Wood), whom he’s neglected for years. But a change of life isn’t an easy matter for a guy like him.

Both Tomei and Wood are very good as the women in Randy’s life, but “The Wrestler” belongs to Rourke, who inhabits the role so fully that despite the fact that you can’t help recognizing him, it hardly seems like a performance. It’s a triumphant return to form after a career that appeared to be pretty much derailed.

And it’s a tribute to the self-effacement of Aronofsky, who simply puts Rourke at the center of the ring and then does his job with a total lack of ostentation. The contributions of cinematographer Maryse Alberti, editor Andrew Weisblum and the other behind-the-camera crew are similarly devoid of frills but dead on.

“The Wrestler” is in the tradition not only of Serling’s “Requiem” but of Arthur Miller’s “Death of a Salesman,” and thanks to both Aronofsky and Rourke it proves an honest and moving portrait of a man in the twilight of a career that’s both made and destroyed him.