Doucoure concedes he almost left the Blues at the time.
He recalled to the 'Breakdown podcast': "After a home game, we had a big quarrel.
"I wasn't happy and I'm an honest person and told him the truth and he didn't like to hear that.
"And the next day I was told I couldn't train with the team. I was told he didn't feel respected by me and then they said I should train with U21 or train alone.
"And then I said I wanted to train alone. I am a professional and can take care of myself.
"Fortunately, it didn't last long. He was fired a week later, so I only trained for a few days.
"The week after, I came back to the team and we won over Arsenal, where I was almost the player of the match..."
Lampard is now in charge at Championship club, Coventry City.