The Belgian, who impressed so heavily during a loan spell with Werder Bremen last season, returned to Stamford Bridge in the summer with thoughts of a first-team place in mind, but quickly found himself behind the likes of Eden Hazard, Oscar, Willian, Andre Schurrle and Juan Mata, whilst Mourinho publicly criticised the 22-year-old's efforts in training.
It was then no surprise that de Bruyne left West London for good in the January transfer window, heading back to Germany with Wolfsburg - but it could've been a different Bundesliga side he joined, as the former Gent playmaker admitted he was close to a move to Borussia Dortmund in 2013 - only for Mourinho to pull the plug.
“Mourinho said no. This is professional football, where there is a lot of money involved. So sometimes strange decisions are made," said de Bruyne.
Bild, the German newspaper who de Bruyne was speaking with, believe that Mourinho spitefully said no to Jurgen Klopp's side because they refused to allow star striker Robert Lewandowski to leave Signal Iduna Park for a move to Stamford Bridge - of course, the Polish international will ply his trade for rivals Bayern Munich next season after the expiration of his Dortmund contract.
De Bruyne would've been seen as a replacement for Mario Gotze, who also left Dortmund for Bayern last season, but Klopp ended up moving for Henrikh Mkhitaryan instead, beating Liverpool to the signing of the Armenian from Shakhtar Donetsk.
Now, de Bruyne will be going up against Dortmund instead, and Klopp is no doubt ruing the missed opportunity to sign the youngster, who has already impressed since returning to the Bundesliga.
image: © Erik Daniel Drost