There is no mention of this in Craig Roberts's enchanting, trueish comedy, but Maurice Flitcroft's quixotic tilt at the Open Championship came right in the middle of a particularly grim period for British golf. No UK player won the tournament between Tony Jacklin in 1969 and Sandy Lyle in 1985. It was, thus, particularly fitting that "the world's worst golfer" should card his unprecedented 121 in the summer of 1976. A crane operator from Barrow-in-Furness, Flitcroft turned up at the qualifying tournament having barely completed a full round on his home course and went on to enter the pantheon of Great British Losers. At least one golfer from the home nation was achieving superlatives (if that is the word).

The most obvious model for Phantom of the Open – a title that doesn't work when spoken aloud – is Dexter Fletcher's unexpectedly strong Eddie the Eagle from 2016. Michael David Edwards was a better ski jumper than Flitcroft was a golfer, but both men tickled the UK public's taste for heroic failures. Like Taron Egerton in the Eddie movie, Mark Rylance plays the protagonist as a sweet-hearted naïf who genuinely believes he has a right to compete against the world's best. Early on, he meets the young Seve Ballesteros, a working-class player who spent more time hacking out of the parking lot than most of his calibre, and gets sound advice about ignoring the snoots and honouring his ambitions, however absurd. This Flitcroft is an avatar of post-imperial accommodation.

Archival interviews suggest the real Maurice might have been a craftier, less ingenuous character, but Rylance’s sweet, on-the-spectrum version works nicely for a film that is so at home to soft edges and Hovis-ad streetscapes. The early sections take us through a kitchen-sink romance of the most charming hue. Maurice meets single mother Jean (Sally Hawkins) and, unconcerned about twitching windows, marries her and becomes a loving father to her son. Twins follow as the busy sixties give way to strikes, inflation and the decade that cinema can’t resist fetishising. Not even incessant needle drops from the Average White Band can distract from the impending redundancies. Saddled with too much time on his hands, Maurice catches a glimpse of professional golf on the telly and, noting a loophole, decides to enter the British Open (as everyone then called it before pedants began insisting on just “Open Championship”).

Simon Farnaby adapts his own similarly titled book on Flitcroft and, once you twig he also wrote Paddington 2, comparisons between the Peruvian bear and the Cumbrian hacker prove hard to resist. Our hero may drive his friends and family bonkers, but he is the purest soul in a world with few properly evil spirits. Even the blazered bigots at the Royal and Ancient are eventually won over and accept Flitcroft as a benign class of menace. As in the Paddington films, this version of England sometimes leans into the fantastic. Interiors have a theatrical boldness. The romantic northern exteriors will require little alteration when adapted for the musical stage show that someone is almost certainly now plotting. Writing Flitcroft's twin sons as world-champion disco dancers feels too much of a concession to seventies-sploitation, but, it transpires, that is precisely what they were.

The film-makers work hard at stretching one moment of (in)glory into a feature-length yarn. Flitcroft, after that 1976 incident, continued to enter tournaments under fictitious names, but, like Mathias Rust, the German kid who landed near Red Square in 1987, he is best known for a brief splurge of headlines from a now remote era. The film does feel a little thin in its later stages, but the inventive performances – Rylance's in particular – keep the film aloft throughout. No bogie. Comfortably a birdie. Not quite an eagle.

Opens on March 18th