If rugby is the game they play in heaven, rugby movies generally come from a lesser place. Between matches in the World Cup, I have been surveying the field, trying to come up with a top five. That is difficult, even if you love the game played with Gilbert's balls. First, there are few movies to choose from; second, many of them are just plain bloody awful – mawkish, didactic, preachy and full of bad rugby.

For a noble sport with lots of drama, this is just not good enough. Most rugby films never really capture the physicality of the game. As the great Tana Umaga told a referee when penalised for an allegedly high tackle: "We're not playing tiddlywinks here, mate. This is a contact sport." The brutal clash of bodies at speed is one of the reasons we watch the game, but that's hard to film, even with professional players doing it for the cameras.

Instead, rugby movies tend to be "inspirational". Take Forever Strong (2008), an American Bible belt film about a drunken rich kid. Rick Penney (Sean Faris) is sent to juvenile hall after he crashes his car and nearly kills his girlfriend. He's the unhappy star of his hard-arse father's Arizona-based rugby team, but a complete brat. His bad attitude persists until he's forced to train with the team his father hates most, Highland. Their coach, played by Gary Cole, is a sort of mystical rugby shaman. The turning point comes when one of the Highland players, an Islander, inscribes the words of a haka on Penney's forearm. The ancient Maori war dance helps him turn his life around. Cue the sappy music. No offence to the haka, but it seems like an odd tool for social work. The film is full of cereal-box slogans and corny speeches, but it does have one or two funny lines. At one point the sullen Penney tries to teach some other inmates how to play the game.

"Man, this is just a bad ripoff of football," says one of the JDs – meaning gridiron. "Actually, Americans ripped off rugby. Then they added sissy pads and helmets," says Penney. Ouch.

One of the better rugby movies is Clint Eastwood's Invictus, set during the 1995 World Cup in South Africa. Although far from his best, it is easy to enjoy, with Morgan Freeman's hammy and spiritual version of Nelson Mandela. The new president thinks rugby can unite his country, despite the fact that the black population hates the game. He takes a strong interest in the team led by Francois Pienaar (Matt Damon). He even frets about how to counter the haka, discussing the problem with his sports minister. "Hmmm, it's very powerful," says the president, shaking his head gravely. The sound of Freeman and Damon mangling the accent probably makes South African ears bleed, but the film is very "inspirational". It's the most sentimental movie in Eastwood's canon, but rugby does that. This great violent contest tends to make otherwise sensible filmmakers drop the ball.

There are so many great films about other sports, so why not rugby? Some might cite Lindsay Anderson's This Sporting Life (1963), with a brooding Richard Harris as a northern bully boy who sees a future biffing people on the field, but that was about rugby league, a splinter code. The game invented at Rugby School in 1845 (actually not, but they codified the rules) has produced little of greatness in cinema. Until now.

A new film from New Zealand is good enough to attract that word. The Ground We Won follows the fortunes of the Reporoa Rugby Club, in the North Island of New Zealand, as it tries  to go through the 2013 season undefeated. The players are nearly all farmers and the club has been through hard times. "No one wants to come and see a team lose all the time," says Phillip Broomfield, aka Broomy, who seems to be captain.

Shot in gorgeous black and white that accentuates the sublime (if foggy) landscape, the film announces its honesty early. In the first scene, the players psych themselves up in the sheds with language that would curdle cream (of which they have a lot, given all the dairy farms).

The film is really about how a cultural pursuit like rugby becomes a way of blooding, educating and initiating young men into the full rites of manhood, Kiwi style. For much of the film, we hardly see a woman. There is work, the tractor, the milking and a number of vivid scenes as a farmer has to pull a calf out of one of his cows – even with a quad bike. On Saturday there is footy, then drinking: ugly, dogged, brutal drinking, the like of which has rarely been seen. To their credit, the players do not curb their behaviour for the camera.

At the same time, the film shows another side, in the gentle and loving way that giant prop forward Kelvin Thomas is raising his twin boys, aged about six, to love the game and uphold its traditions. These scenes are both funny and moving, and they capture a sense of responsibility, as a contrast to the juvenile piss-ups. The Ground We Won is only now starting its run in festivals. It will screen in the Antenna Documentary Festival in Sydney on October 17. It deserves to find an audience.