Giggs believes James still has the talent and raw materials to succeed at Old Trafford and tipped the 22-year-old to keep improving.
“Then what happens is you try too hard and you don't have your natural game. He is still young because he's only really had one season at Swansea. He'd been on loan moves to Shrewsbury.
“He is definitely a player that will get better because he wants to get better, he's a great lad.
"Even if he's not having a really great game he's always putting the opposition on the back foot because they know what he's capable of [with his speed]."