The former Southampton manager was still building his reputation in the game when Bobby Stokes famously stunned the Wembley favourites with the late winner for the second division side.
However, by 1981 McMenemy had got Saints promoted, signed European Footballer of the Year Kevin Keegan and was building a team that would challenge the mighty Liverpool for league supremacy.
So if new wet-behind-the-ears Manchester United chairman Martin Edwards had not bungled his attempt to land the club’s No1 target following the departure of Dave Sexton, McMenemy could have been the one launching a new era at Old Trafford and nobody south of the border would have heard of Alex Ferguson.
McMenemy is back in the spotlight as the two teams prepare to go head-to-head for silverware at Wembley in the League Cup final on Sundat and that last suggestion clearly tickles him. He rewards it with a gratifyingly hearty ex-Coldstream Guard bellow of a laugh.
“Looking back, not going to United was the biggest regret of my career,” he said. “You couldn’t get a bigger club or a better challenge.
Lawrie McMenemy led Southampton to a shock FA Cup win over Man United in 1976
Southampton haven't won a major trophy since their FA Cup triumph
“The way it was handled by Manchester United was to blame. Young Martin Edwards was in charge of the appointment but I found out in the strangest way.
“I was on a tour in Kuala Lumpur and we had been delayed at the airport by the carousels. A disabled man limped up to me and said, ‘Mr McMenemy?’ I nodded. ‘You manager of Manchester United!’ he added excitedly. ‘No, Southampton,’ I corrected. ‘See over there with the curly hair? Kevin Keegan. Go and get his autograph!’ To be honest, I just wanted to get rid of him.
“Then later in the hotel a reporter I knew rang saying the story that United wanted me had broken back home. The Southampton board were next ones on, pointing out I was under contract and sending me away on holiday to give me time to think about things.
“Ron Atkinson went there instead and was given a big bag of money and spent it. I would have probably done the same. Who knows what would have happened, but I do know if the approach had been made while I was in England I could have handled it better.”
So the south coast club continued to feel the benefit and McMenemy took them to second place in the table and left a legacy that continued to prop up the club long after he left.
Paul Scholes and Michael Owen predict Man Utd's team for EFL Cup final
Wed, February 22, 2017
Paul Scholes and Michael Owen have predicted Manchester United's starting XI for the EFL Cup final against Southampton on Sunday
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Paul Scholes and Michael Owen have predicted Man Utd's EFL Cup final team
“I even introduced three-at-the-back to England in the early 1980s,” McMenemy recalled with another deep roll of laughter. “Look at the headlines something like that is still making when Conte does it 35 years later!”
Admittedly, McMenemy had tested the patience of his board by suffering relegation from the top flight soon after his appointment in 1974.
“When we won the cup two years later, I looked up at my ‘olde worlde’ board of directors enjoying their day out sat next to the Queen and thought, ‘That’s for you – thanks very much for standing by me’.
“The cup win meant I was able to start up all those football centres for youngsters around the country. The board said we already had the best players in Hampshire but I knew we needed to think bigger.
“We set up networks in Newcastle, London and Bristol which provided us with Alan Shearer, Jason Dodd, Steve Williams and Austin Hayes, who both played in the 1979 League Cup final, and eventually Gareth Bale.
Ron Atkinson was given the United job over Lawrie McMenemy
“They all came out of those centres which I was allowed to set up. Even today Southampton are still famous for bringing through youngsters – I like to think it all started then.”
When McMenemy did eventually leave in 1985 it was for an inauspicious stint at Sunderland.
“As Jimmy Tarbuck said at the time, what have Lawrie McMenemy and the Titanic got in common? They both should never have left Southampton.” The gentle giant laughs again.
That self-deprecation and warmth has since been channelled into his role as president of the British Special Olympics team. The focus is already on the next Games in Sheffield in August. Last year McMenemy also brought out his autobiography, ‘A Lifetime’s Obsession’.
He lists his greatest achievement as that runners-up spot but says that when dads come up and ask him to sign the autograph books of their sons, he is always introduced as “the man who won the Cup”.
Trophy-wise for Southampton, there has still only ever been the one. Claude Puel has a hard act to follow.