Chelsea's academy has become a goldmine for producing talent on a widescale and while the likes of Reece James, Levi Colwill and Conor Gallagher have cemented their place in the first-team, others have been shipped out on loan or released as a youngster and gone on to excel elsewhere.
With a history of loaning out a whopping 41 players in 2019, it comes as no surprise to see talent slip through the Blues' net and one example of that is when they painstakingly released a 14-year-old Declan Rice.
The Englishman rose to first-team stardom in east London, amassing over 200 appearances for the club and capped his final emotional term with victory in UEFA's Europa Conference League before sealing a £105m move to Arsenal this summer.
If releasing one of the Premier League's finest prospects wasn't enough to churn the stomach, Chelsea lost an even bigger talent when Jamal Musiala was snapped up from under their noses four years ago.
Why did Chelsea let go of Jamal Musiala?
A two-window transfer ban was imposed upon Chelsea in 2019 and several of Europe's prying hands looked to steal some of their top talents. Although winger Callum Hudson-Odoi was subject to a bid from Bayern Munich, the Bundesliga giants also sought to prise Musiala away from west London, as per Sky Sports.
The German-born attacking midfielder, who was 16 years old at the time, turned down a long-term offer from Chelsea in favour of a three-year deal with Bayern.
During that period, it was fashionable for young English players to hone their craft in the Bundesliga with Musiala following in the footsteps of Jadon Sancho and Reiss Nelson, two players who enjoyed fruitful spells in Germany.
Chelsea did receive compensation from Bayern for taking their hottest prospect – reportedly around £170k – but he's developed into one of the best young talents in world football since leaving Stamford Bridge, nothing will cure the devastating blow of having Musiala snatched from them.
How good is Jamal Musiala now?
The "future Ballon d'Or" winner – as dubbed by teammate Alphonso Davies – has already elevated himself towards the realm of being world-class at 20 years old.
The Germany international has combined his ability to glide past defenders, his press resistance and his sharp awareness to become the complete attacking midfielder, who continues to take the world by storm.
Capping off his sensational season in the Bundesliga last term by posting an impressive 12 goals and 13 assists in 33 appearances, Musiala's performances caused the footballing world to stand up and applaud as he came second to Jude Bellingham in the prestigious Golden Boy award.
Once praised by German legend Lothar Matthaus, who compared him to the great Lionel Messi for his ability to excite and entertain on the field, the youngster is delivering on the potential that his formative years promised, and some.
Similar to Messi, gliding past the opposition like they're not even there is a major hallmark of Musiala's game, backed up by how his metrics hold up against his fellow positional peers across Europe's top five leagues.
In the past year, the £83k per-week phenom has delivered a devastating impact in the final third, demonstrating his glowing technical attributes by placing within the top 1% for successful take-ons, top 2% for pass completion, top 12% for assists and top 17% for progressive passes, as per FBref.
Excelling on the domestic stage for Bayern and the international scene for Germany has seen Musiala's value rise exponentially to a whopping £129m (€150m), as per Football Observatory, with the 20-year-old continuing to carve a path to an untouchable legacy, while Chelsea are left wondering what could have been.
