"I don't think I played a game healthy last season. I was probably at 50 or 60% so there's more to come.
"I just think at this place I can improve and I don't think I've nearly fulfilled my potential yet.
"I'd like to be fit as soon as possible with the Manchester United games coming up and obviously the England qualifiers are big games for us.
"I'm working on my fitness every day doing as much as I can, training hard, and hopefully I'll be fit very, very soon."