Starring Shia LaBeouf. In English and Swedish, with English subtitles. Rated 14A

The repeated premise of Borg vs McEnroe is that the still-clanging Battle of the Tennis Titans was between two foes who couldn’t have been more different from each other in temperament, style, or following. But the subtext is really how much they were alike.

Shia LaBeouf is the bigger name here, riffing on his own bad-boy rep as John McEnroe, even more famous in the very early ’80s for his full-court tantrums than for his rocketing left-handed serves. But this Scandinavian effort really belongs to Sverrir Gudnason, virtually unknown outside of Sweden, but a powerfully controlled presence who also happens to have an astounding resemblance to Björn Borg.

Written by Ronnie Sandahl, who’s Swedish, and directed by Denmark’s Janus Metz—best known for the award-winning war doc Armadillo—the generously subtitled movie is weighted strongly to Borg’s side of the net. It spends considerable time with his Romanian fiancée, Mariana (Czech-Swedish star Tuva Novotny, recently seen beside Natalie Portman in Annihilation), and even more with his tough-love coach, Lennart Bergelin, giving Mamma Mia!’s Stellan Skarsgård a rare chance to work in his native language. Through flashbacks, we see how the roughly raised preteen Borg was saddled with class prejudice and with a volatile on-court attitude remarkably similar to McEnroe’s.

We see that impetuousness and resentment drummed out of the boy, to be replaced by ritual and superstition. If the young Björn looks even more like the adult version than does Gudnason, that’s because he’s played by Leo Borg, 13-year-old son of our Scandinavian superman and already a top-seeded player in real life. His scenes stand out powerfully, while Marcus Mossberg isn’t a particularly good match as the adolescent Borg.

The fretful, slightly younger McEnroe is given much less background, and fewer relationships, apart from his doting father (Ian Blackman). Mainly, we see him clubbing and picking fights with rivals like Peter Fleming and Jimmy Connors.

While the tale takes pains to show their parallel development and related stresses, little attention is paid to the commercial aspects of Reagan-era sports. There is one good bit with ad men pitching a brand campaign at the profanity-prone Yank with the slogan “McEnroe Swears By It!” A few more moments like that would have punctured the film’s lopsided structure and overly mournful tone, and thus taken it in the more playful direction of I, Tonya or Battle of the Sexes.

That said, the final Wimbledon showdown, in which resistance proves not quite futile, leads to a surprisingly satisfying end-game.