Originally Posted by tball2day
....Asiics, New Balance and Reebok are wider shoes with good support and may be more comfortable for him than Nike which traditionally are narrow with a steep arch support. But he will be fine with his tennis and his flat feet, good luck!
I'd also add Prince to that list as far as tennis shoes go. I have a very flat foot and the Prince T-22's are extremely comfortable, great fit, stability and cushioning. Went straight of of the box to the court with no break-in needed.