Fellaini followed Moyes from Everton to United last summer.
"I admit that I had a hard time following the dismissal of Moyes," said Fellaini. "I had six seasons working with him and have a lot to thank this man for. But I feel much better prepared for next season.
"I have a learned a lot from that dismissal. But I'm already an eight year pro, playing for six years outside Belgium and have already played 50 internationals, so I have nothing to prove."
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