The 31-year-old Bulgarian, who only made 12 appearances for the Red Devils last season, completed his move to Craven Cottage on a two-year deal on transfer deadline day.
“I said goodbye to the people who deserve it, I couldn’t say goodbye to Ferguson,” Berbatov told reporters at a news conference in Sofia.
“I know he’s the boss but he has lost, to some extent, my respect because of the way he treated me.
“I don’t think I deserved such treatment at United, not playing in the last year.
“I went probably 15 times to ask the coach if he needed me. Every time I was told that I’m an important player and should not leave but then again I was not in the team. Maybe I should have gone when he left me out of the squad for the Champions League final.”
Berbatov joined United from Tottenham Hotspur in a £30m deal in the summer of 2009 and went on to score 56 goals in 149 appearances for the Red Devils.
But the striker fell behind the likes of Wayne Rooney, Javier Hernandez and Danny Welbeck in the pecking order at Old Trafford last season.
“He tried to explain to me that the team will be using a more direct style, with more speed,” Berbatov continued. “But I’ve never been among the fastest players. I like to hold the ball, this is my style.
“I found it hard to accept his decision, I still have my dignity. I scored many goals, I won the league two times and I was the league top scorer, so it’s not bad.
“I’ll have no problems playing against United as this already happened in my career. But there’s no point to look back again.”
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