A regular under Frank Lampard, the England fullback was dropped by the new German manager.
But the immensely talented 21-year-old fought his way back to become a regular under Tuchel, eventually winning the Champions League and making England's squad for the Euros.
"We had Frank Lampard and I was very lucky to play the majority of the games under him, but when our new manager came in our style of play and formation changed," said James.
"The first few games I found myself out the team. That was quite difficult to deal with. I had to adapt and learn. It's hard when a new manager comes in mid-season, I've never had it before. It was a big learning curve.
"You have to accept the decision and work hard and try and prove to the manager that you should be playing and you're definitely capable of playing.
"These moments come around quite often in football. Things happen so fast, I don't really get advice from anyone. I was just wanting to train and carried on working hard, and when I got more opportunity I knew I had to take it."