Speaking to the official site physiotherapist John Stannard said: "Clark may have a small hernia. We took him for a scan on it last Tuesday and we will know tomorrow (Tuesday) if he will require an operation. It's only a small problem though and he will be off a couple of weeks."
Clark, who joined from Brentford on a frebbie, has yet to play for the first team and made 8 appearances for Blue Square South team Welling United on loan last season.