Since the takeover of Todd Boehly in May 2022, Chelsea have spent over £1b on transfers as they aim to close the gap produced by the likes of Manchester City and Liverpool in recent seasons.
Players such as Enzo Fernández and Moises Caicedo have both joined the Blues for fees over the £100m mark – with the latter breaking the English transfer record after his move from Brighton and Hove Albion in the summer of 2023.
The pair are most often utilised at the base of boss Mauricio Pochettino's midfield, with Cobham Academy graduate Conor Gallagher the most frequently used player who plays slightly ahead of the two £100m players.
Despite their recent dealings in the transfer market, the club may have missed a trick by not keeping hold of two midfielders who were on their books and have both gone on to be top-quality Premier League midfielders.
Declan Rice stats since leaving Chelsea
Declan Rice was on the books at Chelsea between 2006 and 2013, before being released and subsequently joining fellow Premier League side West Ham United – featuring for their academy sides.
The midfielder made his Premier League debut for the Hammers in 2016 – quickly making a name for himself during his time at Upton Park and the London Stadium.
Rice established himself as a regular for West Ham, going on to make 245 appearances for the club before leaving to join London rivals Arsenal for a deal rising to £105m with add-ons.
Declan Rice
Arsenal
£94m
Levi Colwill
Chelsea
£47m
Reece James
Chelsea
£43m
Michael Olise
Crystal Palace
£43m
Mason Mount
Man Utd
£38m
Nathan Ake
Man City
£34m
The 25-year-old has been brilliant since he arrived at the Emirates as he's been instrumental in Mikel Arteta's attempt to end the Gunners' 20-year drought without a league title.
He's played 34 times in all competitions for Arteta's side, scoring four times including a wonder striker against his former side at the London Stadium last Sunday.
Despite his start to life at Arsenal, Chelsea made a bigger mistake by letting a talented midfielder leave in 2013, before joining a Premier League rival and becoming one of the best players the division has ever seen.
Why Kevin De Bruyne left Chelsea
Kevin De Bruyne joined Chelsea from Belgian side Genk for £6.7m back in January 2012 – however, the midfielder was never really given a consistent run in the first-team at Stamford Bridge.
Commenting on why they had to let him go, the infamous Jose Mourinho stated of De Bruyne and Mohamed Salah: "To be honest, they left because they wanted to leave. They left because they didn't want to wait.
"History proves that their option was good because they've had the careers they have and reached a high standard, but sometimes kids make decisions like that because they can't wait, or they don't have the patience to be calm and to wait for the right moment. Sometimes their career goes in the wrong direction.”
The Belgian ended up only making nine appearances during his time at the club, before joining Bundesliga side Wolfsburg permanently for £17m in 2014 – a deal that made the club profit at the time, but looks to be a bargain given his career since.
Whilst he enjoyed a brilliant season for the German side, Manchester City is where De Bruyne has made his name and cemented himself as one of the best midfielders in Premier League history.
He's made 366 appearances during his time at the Etihad, providing 161 assists for his teammates – branded as an "assist machine" by the Independent's football correspondent Richard Jolly.
Despite his long-term injury lay-off with a hamstring injury, De Bruyne has returned to action in the new year as if he'd never been away creating four assists in his first six Premier League games back.
Chelsea may have two very good young midfielders within their team. However, they could've saved themselves over £200m had they trusted Rice and De Bruyne during their development at Stamford Bridge.