The 15-goal striker has been told to wear the hefty plaster cast protecting his fractured wrist for another three weeks.
Les, who did the damage in a freak accident at home, explained: "Unfortunately I've got to keep this plaster on for another three weeks before they can take it off and have a look if it's healed properly.
"Hopefully it will be okay. They will then put a temporary one on it so I don't fracture it again.
"We'll see where we go from there but playing this season is out of the question."
It's a sad end to the season for Les who looked nailed-on to bag 20-plus goals this season. He had 14 when he suffered a head injury against Everton and although he returned for the Worthington Cup Final, he's only netted one more since.
"Obviously it's a big disappointment," he added. "I was at the game against West Ham and kicking my heels on the sidelines but there is not a lot you can do about it.
"The season started so well for us and continued up until the Worthington Cup Final but since then things have turned the other way for us. Up until then I'd say, yes, it was a great season, but not so much after."
Les Ferdinand has conceded he will be out for the rest of the season.