United completed a £35million transfer for the former Ajax star, who remains their only incoming signing of the summer so far.
"He comes from a top club in Holland where he has risen through their academy," Phelan told FourFourTwo.
"He's got all the Ajax traits: good possession, control on the ball, skills. He broke into the international setup, so he's in with an up-and-coming Holland side now, which should push him on.
"He's 23 and that age is important. It'll be a challenge for him in the Premier League this year but he has a good eye for goal and is a good athlete with energy. He's halfway between a midfielder and a forward."
Phelan believes Solskjaer has the ideal mix of youth and experience in the squad.
He added: "The seasoned professionals and people like myself always want success. We've not got forever and that can make me harsher, a little bit edgy, impatient and grumpy because I want success now.
"But those experienced professionals are so important. They demonstrate good habits and set good examples to the young lads, even though at 30 in the real world they are still young men."