"I'm delighted he's doing well down there, he's a Middlesbrough player and we want him in our first team eventually and the experience he's getting is doing him a lot of good," the Boro boss told the Journal.
"He's a young player with great potential, but that's all it is. He's still a long way to go and we're keen to give him as much league experience as possible to help his development and to also help out Sunderland.
"Hopefully, when he does come back, he will return a better player."