In an exclusive interview with MUTV, Gradi - the man who has overseen the development of some top-class talent at Gresty Road - not only praised the young forward but also Sir Alex for the decisive way he acted during the negotiations.
"Nick Powell is a match winner," asserted the Crewe supremo. "He doesn't rely on other people to make the goals for him. He's not a six-yard box player. In fact, we've been trying to encourage him to get in that six-yard box more. But he picks the ball up, runs at people and finishes with a goal. He wins matches on his own.
"I used to watch him in Crewe's Under-16s, training on a Monday night, and he'd hit them in from everywhere. When he joined us and came with the first team, he was a little more reluctant to do that. Perhaps he lost a bit of confidence doing that and he was playing in a more central role for England, where he was passing the ball.
"We managed to persuade him not to do that if you can score. Don't become a 'steady Eddie' if you can become a special player. He scored a terrific goal at Wimbledon for us and it reminded us of the goals he used to score for the Under-16s, going on from there to score some terrific goals."
According to the Crewe supremo, Powell is a unique talent - different to players like Dean Ashton and David Platt who've rolled off the conveyor belt at Gresty Road. "We've had some terrific players at Crewe who went on to play for England, but Nick's not the same as any of them. He does a similar job to [current England player] Alex Oxlade-Chamberlain."