Sancho Guardiola Garcia Manchester City GFXGetty/Goal

First Sancho, now Garcia: Why don't Man City's young stars want to play for Guardiola?

Phil Foden's role in helping Manchester City into the quarter-finals of the Champions League provided yet another ringing endorsement for the club's academy system.

Joining the club as a six-year-old, Foden has worked his way through the City youth system to earn his place in the starting line-up for Friday's 2-1 win over Real Madrid in what was one of the most significant European nights in the club's history.

With the effects of lockdown meaning squad sizes remain bloated, fellow City-supporting youngsters Taylor Harwood-Bellis, Tommy Doyle and Cole Palmer were also among the substitutes at the Etihad Stadium.

That represents a strong percentage of youth-team players for a club that has invested heavily to build a first-team squad that it hopes can go all the way to the final in Lisbon.

But it was also a case of what might have been.

Teenager Eric Garcia would likely have started against Los Blancos had he not a dropped a bombshell in the days leading up to the game that he would not be signing a new contract with the club. A move back to boyhood club Barcelona now looks likely.

Meanwhile, another highly-rated Spanish academy product, Brahim Diaz, was sitting on the visitors' bench after leaving the Etihad Stadium 18 months ago.

Jadon Sancho, another who played in the same City youth team, could be on his way back to Manchester in a €120 million (£108m/$141m) deal this summer, but that is only if Manchester United can reach a deal with Borussia Dortmund.

It would appear to be a worrying trend that a number of star graduates that are coming through the academy are starting to look elsewhere, with Foden the exception to the rule.

As a diehard City fan, the 20-year-old has had to be patient when waiting for his opportunities. But after showing determination on the training pitch and giving everything in 74 appearances - a number of which were just short cameos - he earned his starting berth for the biggest match of Pep Guardiola's season.

The Catalan coach does not hand out appearances for nothing - each one has to be earned by showing you are better than the other, sometimes more senior options in your position.

Foden could easily have left the club - either permanently or on loan - but his resolve to become a legend at the club that he loves kept him battling for his City career.

Others have taken a different approach - some working out while others have not - and there is no guarantee that leaving is a route to success.

Certainly Sancho can have no regrets about taking the bold decision to quit City, though his departure was far from straightforward. The England international felt he was ready for first-team football and was not prepared to wait any longer for his chance to impress.

Jadon Sancho Manchester CityGetty Images

When the winger was left out of a pre-season tour to the United States in the summer of 2017, he made his unhappiness clear by skipping a number of training sessions back in Manchester.

Sancho was eventually sold for €9m (£8m/$10m) - with a further 15 per cent to come from any sale to United after he took the Bundesliga by storm.

His success prompted further exits from the Etihad to Germany - with mixed success. Wales international Rabbi Matondo has started to break into the starting line-up for Schalke, but others have fared less well.

Brahim's decision to leave was also fuelled by a wish to gain more game time, but choosing Madrid was a curious call.

A year-and-a-half after his €17m (£15m/$19m) move to Santiago Bernabeu, the 21-year-old has played just 10 hours of football for the Spanish giants and seems further away from becoming a first-term regular than when he was at the Etihad.

Garcia is the latest to want away and probably the most frustrating for the City hierarchy.

Eric Garcia Pep Guardiola Manchester City 2018-19

The 19-year-old, who joined from Barca’s La Masia academy in 2017, has impressed youth coaches and Guardiola's first-team staff alike with his maturity and intelligence.

With a long-term injury to Aymeric Laporte and inconsistency from John Stones and Nicolas Otamendi, Garcia has taken his opportunity to cement his place in the squad during the course of the 2019-20 campaign.

Following the Covid-19 shutdown, the teenager has taken another leap forward and emerged as Laporte's most trusted partner - starting the FA Cup semi-final against Arsenal and Premier League clash with Liverpool.

His decision to reject a contract extension, then, has come as a shock, particularly after the trust and time that has been put into the young defender.

City have not given up hope that he may change his mind, with Barca seemingly unwilling to match their €33m (£30m/$39m) asking price this summer while there is potential for his career to stagnate while he sits out next season waiting for his contract to run down.

But Garcia's decision is also based on a desire to return to his boyhood club and the potential to be the long-term heir to iconic centre-back Gerard Pique.

Eric Garcia Manchester City Barcelona GFXGetty Images

It is a body blow to City and their hopes to have a steady stream of players transferring from the academy to the first team, despite Garcia's exit potentially opening the door for another former youth-team star Tosin Adarabioyo, who has had a solid spell on loan with Championship side Blackburn Rovers, to break into Guardiola's group next term.

Garcia is unlikely to be the last to leave, either.

Highly-rated Dutch winger Jayden Braaf continues to be coveted by RB Leipzig, though the 17-year-old has trained with Guardiola's squad since football returned in June.

Homegrown forwards Charlie McNeill and Jamie Bynoe-Gittens, meanwhile, look set to depart this summer, with Manchester United and Dortmund respectively leading the races for their signatures.

That comes 12 months after striker Noah Ohio turned down the chance to sign professional terms with City and instead move to RB Leipzig, where the Netherlands youth international has enjoyed a prosperous first campaign.

It is clear that City's highly-rated academy is producing quality players. But getting them into the first team has not proven to be quite as simple.