Jose Mourinho has defended Chelsea's decision to sell Kevin de Bruyne in 2014.
The Belgian midfielder moved to Wolfsburg for a fee of £18m, but could now be on his way to Manchester City for £57m.
"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," Mourinho told Sky Sports News.
"If De Bruyne stayed here, not happy and not motivated, and we'd sold him after a year, we'd have got less - 50% less - than we sold him for.
"But, if he was at Chelsea and not at Wolfsburg, he wouldn't have reached this level. It was like a wall, a block."
The 23-year-old made just nine appearances for Chelsea before moving to Wolfsburg.
