He was the Cardiff boy who turned Fourth Division Swansea City into top-flight title contenders.
Yet if he had got his way, John Toshack's glorious spell in charge of Swansea would never have happened.
After eight years at Liverpool, former Cardiff City striker Toshack wanted to return to his home-city club as a player-coach.
Little did the Bluebirds know that when they said no to a Toshack comeback in 1978, they had triggered the start of a golden period in the history of their south Wales rivals.
Toshack had at one stage been set to leave Liverpool for another top-flight club, Leicester City, but failed a medical at Filbert Street.
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"I had a thigh problem but I was still able to play," he tells BBC Sport Wales.
"I remember going to Cardiff and speaking to Jimmy Andrews, who was the manager at the time.
"I offered myself. I had been told I could get a free transfer from Liverpool because of the condition I had.
"I still had a year or 18 months on my contract, but I had great difficulty with the Saturday-Wednesday-Saturday slog at Liverpool because we were in Europe every year.
"I thought I would be able to contribute something as a player-coach at Cardiff - but Jimmy Andrews wasn't for it.
"I don't know whether looking back he felt a little bit that his own job might be in danger. That never crossed my mind at the time.
"I felt it would give me a chance to play and learn the management ropes at the same time, but Jimmy put the blocks on it and I was very disappointed."
As Cardiff's door closed, another opened 40 miles down the road.
Toshack was in Swansea to take part in a sports forum alongside rugby union star Barry John.
Among those in attendance was then Swans chairman Malcolm Struel.
"We got talking," Toshack recalls. "One thing led to another and suddenly Swansea offered me a job as player-manager.
"The more I thought about it on the way back to Liverpool, the more I thought it was a good idea."
'Toshy, Toshy, what have you done?'
With his move to Vetch Field agreed, Toshack made the short trip from his Formby home to Rochdale to watch his new club in action, with Liverpool team-mate Emlyn Hughes coming along for the ride.
"It was the Fourth Division and Rochdale were bottom of the league," Toshack says.
"We didn't know where we were going but we saw the floodlights and that led us to the ground. There was only a small crowd - only about 2,000 I think. Swansea lost 1-0 to a goal in the last 15 minutes.
"I remember going back to Formby with Emlyn in the car and him putting his hand on his head and saying, 'Toshy, Toshy, what have you done? This morning you were a player in the squad of the European champions and now you are manager of the team that's just lost to the worst side in the Football League'."
Nobody could have dreamt then that Toshack's Swansea would be playing a league game at Anfield just three-and-a-half years later.
But the Welshman's appointment inspired the Swans, who reached the First Division - now the Premier League - for the first time in their history courtesy of three promotions in four seasons.
In their maiden top-flight campaign, 1981-82, Swansea were top of the table in March and were firmly in the title race until a late-season dip saw them finish sixth.
A year later Swansea were relegated, prompting a decline which was as rapid as their rise had been, but Toshack's time will not quickly be forgotten.
That sparkling spell was all the more remarkable because the boss was Cardiff born and bred, and had spent the early part of his career playing for the Bluebirds.
"I grew up within walking distance of Ninian Park. In those days Swansea were the enemy," Toshack concedes.
"I played in Cardiff-Swansea derbies and was 100% Cardiff on those occasions, but later on in life things changed.
"My Cardiff connections crossed a lot of people's minds when I went to Swansea because of the rivalry.
"In my time at Swansea it was Cardiff who became the enemy, but I have lots of time for both clubs now of course."
Toshack, 70, will be at the Liberty Stadium on Sunday to see the first meeting of Wales' top two clubs in five-and-a-half years.
And the former Real Madrid boss believes home advantage could prove decisive.
"I can see Cardiff battling away and being difficult to beat but maybe just lacking that bit of spark in the last 30 metres, which possibly Swansea have got," Toshack says.
"Swansea had a terrific start to the season and have now had a blip.
"But I think when it comes to the crunch, I would probably always go for the home team."