But the Scot admits following Sir Alex Ferguson was "near impossible".
"It was a step into the unknown and, looking back now, it was near enough the impossible job," he told the Mail on Sunday. "But it was the right job for me. I'd been at Everton for more than 11 years. We'd qualified for the Champions League, got to an FA Cup final, I'd been voted manager of the season three times. I was among the most experienced managers in the Premier League. United had always had British managers.
"I was devastated to lose the job because it was something I felt I could make a real success of. We knew it was going to take time to make the necessary changes. It was going to take time to evolve. But we were in the process of making other important changes. In the end, I don't feel I was given time to succeed or fail."
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