Silva said: “It's really hard and it's becoming harder. In my opinion, it [the gap] is getting bigger, partly because the Premier League is so competitive.
“Last season we saw how much clubs were fighting not be relegated, how much they spent in the January market. It was unbelievable.
“Some clubs are more prepared for that. The Championship is tough, but look right now: Leicester are top They are a Premier League club and were for 10 years. For some it is not so difficult [to stay up], but for others it is, and Fulham and Norwich are good examples from their years of up and down."