Crowd favourite Smith was sold to Portsmouth to balance the books at Vicarage Road while boss Malky Mackay also lost Jobi McAnuff, Mike Williamson and Tamas Priskin.
But Smith said: "I've played with Malky, seen him as a coach and been a player under him so I loved working with him.
"It's not going to be easy and they have to replace some experience, but Malky's a shrewd guy and he's got some good loanees in and I'm sure that will improve things.
"The club has got a lot of good young players, I don't think they'll be looking down - I'm confident the young players can progress."
Source: Team_Talk