BLACKBURN Rovers striker Matt Jansen may need an operation in order to cure a knee problem.

The 27-year-old forward was ruled out of Saturday's thrilling 2-2 draw with Liverpool after a scan revealed he had torn his cartilage.

And if the problem deteriorates over the next few weeks then Jansen may need a clean-up operation which would rule him out of Mark Hughes's first team plans for up to a month.

The club's medical staff are still hopeful that surgery can be avoided after drawing up a rehabilitation programme for the popular striker.

But Jansen himself could have the final say if the injury shows signs of getting any worse over the next few weeks.

"Matt has got a slight tear in his cartilage and he's currently undergoing rehabilitation that should hopefully resolve it," said club doctor Phil Batty.

"We feel that should be enough to resolve the matter until the end of the season but you can never be certain in these situations.

"Ultimately, the person who'll decide whether an operation is needed or not will be Matt himself.

"It's down to how he feels it's affecting him, but as things stand it's not a bad tear."

News of the injury could hardly have come at a worse time for Jansen given that he only recently forced his way back into the first team.

Before Saturday's meeting with Liverpool, the former Crystal Palace star had figured in four of Rovers' previous five Premiership matches under Hughes.

And he recently scored his first Premiership goal in 12 months when he netted the winner against Portsmouth on September 18.

With Rovers struggling for goals up front, Hughes needs all the fire-power possible at his disposal going into the games against Norwich, Manchester City and Birmingham -- three sides who are also scrapping for points at the wrong end of the Premiership.

Norwich's 1-1 draw with Manchester City last night meant that Rovers slipped back to the foot of the table.