Ryan Giggs, Paul Scholes, David Beckham and others were able to meet Alex Ferguson's standards at Manchester United because of iconic youth coach Eric Harrison, according to their fellow 'Class of '92' graduate Chris Casper.
Harrison passed away on Wednesday at the age of 81 and the world of football was swift to pay tribute to the man who helped forge one of the greatest dynasties the sport has seen in Britain.
As well as Giggs, Scholes and Beckham, Gary Neville, Phil Neville and Nicky Butt all came through United's academy in the early 1990s, going on to play a huge role in one of the most fruitful periods in the club's history.
Giggs – the most decorated British player ever – went on to overtake Bobby Charlton as United's record appearance maker, while Scholes is third in that list and Gary Neville captained them for six years.
All six players were nurtured by the guiding hand of Harrison, and Casper – who started alongside Giggs, Gary Neville and Butt in the 1991-92 FA Youth Cup final – thinks the coach's similarity to Ferguson was vital.
"They were very similar, with the values and standards," Casper told Omnisport. "I think the work ethic they demonstrated every day, the standard they set, the expectations the manager [Ferguson] set – it came from Eric, really.
"Eric was the first person to work with you when you got into the training ground as a 16-year-old, sometimes even before that when you were 14 or 15.
"He set the tone really, but there was nothing different about the way Eric was and the way the manager was. It was just that progression. They were similar in many ways.
"It was obviously driven by the manager, he picked you for the first team, but it was started by Eric. He gave you the confidence to believe in yourself.
Flashback to the early 90s... as Beckham, Giggs, Scholes, Butt and the Neville brothers ran riot in the youth team.https://t.co/0IWEsaZZ5K— Manchester United (@ManUtd) 8 July 2015
"He was our mentor, teacher, leader. He helped shape us not just as footballers, but people as well.
"I think a lot of it is values, the way you behave, portray yourself, the way you act, also having clear messages - Eric wasn't one for mincing his words, and you really appreciated that from him."
Scholes is the latest to take up a full-time position after being appointed the manager of League Two's Oldham Athletic on Monday, and Casper – now sporting director of Salford City, the club part-owned by Giggs, Scholes, Beckham, Butt and the Nevilles – thinks they will all aspire to manage United one day.
"He [Scholes] had such a long career, you always hoped he'd go into that side of things and use his experience and knowledge," Casper added.
"I don't think Paul will change [his personality] in the dressing room. I think he'll set the standard, a very high standard.
"It's good that Paul, Ryan, Nicky and Phil are getting the opportunities to put something back into the game, helping people, using their experience and shaping their football clubs, squads and teams.
"Man United is the biggest, or one of the biggest, jobs in world football. I'd imagine they'd all have aspirations to manage the club one day.
"It'd be good to have that continuity and have that experience of what it actually takes to be at Man United and be part of something that'd be great moving forward.
"They're all getting experience, hopefully they'll get the opportunity to manage it [make the jump up to United's level]."