Mason Mount's move to Manchester United indicative of the chaos engulfing Chelsea

Midfielder was expected to spend his best years at his boyhood club - instead he has strengthened a direct rival

Mason Mount is set to leave Chelsea for Premier League rivals Manchester United. PA

One-club footballers have always been a rare breed in the modern game. For the biggest teams in Europe, though, the hope is that your elite Academy players – the tiny fraction who progress to, and cement a place in, the first team – will spend the best years of their careers at their boyhood clubs.

Even at Chelsea, where frequent player turnover has been part of their model ever since previous owner Roman Abramovich took over the club in 2003, having a core of homegrown players in the starting XI has always been the ultimate goal.

And yet, the poster boy from Chelsea's best generation of Academy graduates is on his way to Manchester United. While others have left before, there is something more significant and symbolic about Mason Mount's exit.

Chelsea may have regrets about selling Fikayo Tomori and Tammy Abraham to AC Milan and Roma respectively in 2021, given the subsequent money they have spent on rebuilding the defence and their long-running struggles for goals, but at the time, neither were first-team regulars.

Mount, on the other hand, immediately established himself – first as a regular, then as arguably Chelsea's best player. An impressive debut season in 2019/20 was followed by a superb 2020/21 campaign as Mount played a key role in Chelsea's Champions League triumph.

His third term for the Blues was his most productive, with 29 goal contributions – 13 goals, 16 assists – even as the club dealt with unprecedented instability following UK government sanctions imposed on Abramovich. Mount was named the club's Player of the Year for a second successive season.

Mount did struggle for form and fitness last season as Chelsea recorded their worst campaign in almost 30 years, but his long-term importance to the club had never felt in question. That was until a breakdown in talks over a new contract – Mount's existing deal expires next summer – put Chelsea in a vulnerable position.

Add to that the club's need to balance the books after spending more than £600 million on players in the past 12 months, and a good offer for Mount was always going to open the door to the previously unthinkable situation of the England midfielder playing his best years elsewhere.

Chelsea 2022/23 season ratings

Now a player who should have been a symbol of stability and longtermism – the sort of values the new owners have often spoken of but so far struggled to support with action – is instead indicative of the chaos engulfing Chelsea.

Mount is not leaving for Real Madrid or Bayern Munich, a European super club where domestic titles and Champions League contention are annual occurrences and whose ambitions infrequently collide with Chelsea's, but for a United side in direct and immediate competition with the Blues for top four places, cups, and ultimately challenging Manchester City's dominance.

That the 24-year-old views his future at Old Trafford and United as the more attractive project, rather than remain and help rebuild his boyhood club from the rubble of last season, should set off alarm bells at how drastically Chelsea's stock has fallen, even from within its own walls.

Financial Fair Play may be cited as the primary reason for a willingness to sell, but Chelsea always wanted Mount to stay and offered the midfielder a £200,000-a-week contract to commit his future to the club.

With that final contract offer rejected and Mount on his way out, it's a bitter blow for new manager Mauricio Pochettino. Mount, one of the best pressing midfielders in the Premier League, would have been ideally suited to Pochettino's preferred style of play, so it's no surprise the Argentine was desperate for the England international to stay.

There were always going to be several significant outgoings from Stamford Bridge this season, and the transfers of Mateo Kovacic to City and Kai Havertz to Arsenal in particular would have stung the Chelsea faithful. Mount, who joined Chelsea at the age of six, represents a different sort of exit entirely.

The faint hope is that the Chelsea bosses know what they're doing. Given recent evidence, that's probably not the case.