Wests Tigers hooker Robbie Farah has undergone surgery on his injured knee, leaving coach Jason Taylor in a mad scramble to fill the No.9 jersey.

Farah will miss the next four to six weeks after having arthroscopic surgery for a meniscus tear in his right knee suffered in Saturday’s 30-all trial draw with Cronulla at Campbelltown Stadium.

The NSW Origin rake heard a “pop” during the first half but the severity of the injury wasn’t discovered until post-match after he had cooled down.

The tear is in the same knee Farah had surgery on for a ruptured ACL in 2014.

The Tigers, after having an abundance of No.9 options in the pre-season, suddenly have a massive headache as they look to fill the position for their season-opener against the Warriors on March 5.

Manly discard Matt Ballin is still two months away from his return from an ACL tear while utility Dene Halatau will miss the first round through suspension.

It means Taylor will likely turn to 21-year-old Manaia Cherrington to fill the void.

Cherrington played 11 NRL games after debuting last year and travelled to England as part of the New Zealand touring party without playing a Test.

While highly rated, the youngster is not yet an 80-minute player meaning the Tigers will likely use him in tandem with former Australian Schoolboys rake Jacob Liddle for round one.