Chelsea star Willian believes Manchester United will be a stronger club with Jose Mourinho as their new manager, but expressed his sadness that the Portuguese coach left Stamford Bridge in December, reports the London Evening Standard.

Willian admits the Portuguese's departure from Chelsea left a bitter taste in his mouth.

"Jose is one of the most successful coaches in the world and Manchester United will be stronger with him as manager," Willian is quoted by The Sun as saying.

"I played some of my best football under Mourinho. He is a special coach and I have a great relationship with him.

"Winning the Premier League with him was one of the highlights of my career. I was sad things didn't work out after that."