Manchester City star Kevin De Bruyne was never given the opportunity to shine at Stamford Bridge.
He was signed by Chelsea from Genk for £6.7m in 2012 but made only three Premier League appearances before moving to Wolfsburg.
De Bruyne, 26, is now considered one of the best midfielders in the world and is thriving under Pep Guardiola at the Etihad.
Manchester City are already eight points clear at the top of the table and the Belgian midfielder has been directly involved in 13 goals in his last 14 games in all competitions.
Jose Mourinho's Manchester United are their closest competitors but the Portuguese manager is not remembered so fondly by De Bruyne.
Mourinho, who has managed Chelsea on two separate occasions, deemed the Belgian midfielder wasn't good enough to be in the first team.
In 2015, Mourinho said: "With De Bruyne, if you have a player knocking on your door and crying every day he wants to leave, you have to make a decision. At that time, Chelsea did well.
"He was not ready to compete. He was an upset kid, training very bad."
De Bruyne reveals what he said to Mourinho in 2013
In an exclusive interview with The Times, De Bruyne has reminisced about his unhappy time at Stamford Bridge.
He made only two Premier League starts before being sold to Wolfsburg in January 2014.
“I just said [to Mourinho] I can play,” De Bruyne told The Times on Saturday.
“I have no statistics — two games, what do you want me to do? I had a feeling I wasn’t even going to play. Even if he [Mourinho] said you’re going to play more games, from two games I was maybe going to go to five. It was, for me, a good decision to leave [for Wolfsburg for £18 million].
“For them, in the end, it was also a good decision. They sold me for more money for a player who didn’t play. I played in Germany for a good year [at Bremen on loan], so that’s why my value went up. But I went to Wolfsburg just to play football. I hate it when I cannot contribute."
Mourinho's decision to allow De Bruyne to leave will surely be remembered as one of the worst decisions of his managerial career.
He is unquestionably one of the best footballers in the world and will strut his stuff at the 2018 Russia World Cup next summer.
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