"But now he's going to get an opportunity to play. I would be a liar if I said he had shown he can perform in the Premier League. If he had he'd have been playing. I think he needs to adjust and it's been hard.
"But if he comes in and goes on a little run now, works hard and shows he can score goals, then he can get the opportunity to play.
"It's always a gamble when you take players from the Championship into the Premier. You hope they hit the ground running but David's not had a lot of chance to be fair.
"He's been unfortunate, especially once we've been playing this system with one up. I want him to do well, I bought him, nobody wants him to do well more than I do.
"Only time will tell. Hopefully he will prove a success - it's up to him."