Flitcroft became notorious after hitting a score of 121 in the qualifying competition for the 1976 Open Championship—the highest score recorded at the Open Championship—and by a self-professed "professional golfer". Subsequently, he gained significant media attention, being referred to as "the world's worst golfer". Following the 1976 Open, the rules were changed to prevent Flitcroft from attempting to enter again. Undeterred, he regularly attempted to enter the Open and several other golf competitions, either under his own name or under pseudonyms such as Gene Paceky (as in paycheque), Gerald Hoppy, and James Beau Jolley. Flitcroft was married to Jean (died 2002) by whom he had two sons—one of whom caddied for him.
He is the subject of a biography, The Phantom of the Open, by Scott Murray and Simon Farnaby, published by Yellow Jersey Press in July 2010.
In his obituary, The Daily Telegraph commented thus:
- Maurice Flitcroft ...was a chain-smoking shipyard crane-operator from Barrow-in-Furness whose persistent attempts to gatecrash the British Open golf championship produced a sense of humour failure among members of the golfing establishment.
The 1976 Open Championship
Flitcroft had golfing ambitions well above his ability and came to notoriety in 1976 when, posing as a professional golfer, he managed to obtain a place to play in the qualifying round of The Open Championship—despite his previous experience amounting only to some hacking around on playing fields near his home. Flitcroft recalled, "I was looking to find fame and fortune but only achieved one of the two."
When he discovered, to his shock, that any amateurs entering competitions had to have an official handicap—something he lacked—he simply declared himself to be a professional. It was in the same 1976 Open that a young new player, the 19-year-old Seve Ballesteros first came to the public's attention. Flitcroft prepared for the tournament by studying a golf instruction manual by Peter Alliss which was borrowed from his local library. He further studied from instructional articles by the 1966 PGA Championship winner Al Geiberger, and honed his skills on a nearby beach.
His deception (and ineptitude) were uncovered when he managed to card a 49-over-par 121—the worst score in the tournament's history; some of the other professionals playing with him were so angry that they successfully demanded a refund of their entry fees. It seems that none of the professionals noticed that his gear comprised only a red imitation-leather bag and half a set of mail-order clubs. As a result of his abilities, he became known as "The Royal & Ancient Rabbit".
In a July 2006 article in Golfonline, Flitcroft said, "I was in show business. I toured with a revue, and I used to jump into a tank on the stage, I was a stuntcomedy high diver. The revue used to tour all the country and I would dive into this tank. It wasn't all glass, just the front so the spectators could see what was going on under the water." 
After his initiation into celebrity golf, Flitcroft briefly became a C-list celebrity and had various golf trophies (usually those celebrating poor play or egregious mishaps) named after him; he also had the distinction of having the "Maurice Gerald Flitcroft Member-Guest Tournament" named after him by the 1988 Blythefield Country Club in Grand Rapids. Buddy Whitten, Blythefield’s head pro stated that, “It started as a lark, but most people can’t break 90 so they relate more to Maurice than they would to a touring pro.” By the time of the 22nd Maurice G. Flitcroft Member-Guest Tournament, which was held in May, 2000, the club had featured a green with two holes so that even the most errant of approaches were potentially rewarded. If this wasn't enough another green had a 12-inch (300 mm) cup.
In 1988, Flitcroft himself was flown to Blythefield to play in the event. He is reported as having told the members there that it was the first time he and his wife had been out of the house together “since their gas oven exploded.” Whitten further said, “It was a different sort of experience, I’d never met a crane operator from England. But his game had gotten a little better than I expected. I think he shot in the low 90s.” Flitcroft said of his performance, “I wasn’t playing too well. Some faults had crept into my swing. But I hit a lot of good shots.”
Flitcroft retired from Vickers in the 1970s and devoted himself to his golf—but was reduced to the ignominy of once again playing on local fields, having been banned from every local golf club after sneaking into their grounds to play without permission.
Many years after his rise to fame, Flitcroft still received post which had been addressed simply to: Maurice Flitcroft, Golfer, England.