De Visser says Vitesse coach Fred Rutten has rescued the young fullback's career.
"The best example is perhaps Patrick van Aanholt. Last season he had a dramatic year. John van den Brom didn't treat him well and failed to work with him. That was a big mistake.
"But then Rutten went to work with him and now he's come on in leaps and bounds. Therefore I am, but also Chelsea, so happy with Rutten as a trainer."