Australian Jack Robinson has been forced out of the upcoming Margaret River Pro with a knee injury, denying the world No.2 the opportunity to defend the title at his home break.

The 25-year-old Robinson damaged his left knee in a round-of-32 loss to young countryman Xavier Huxtable at last weekend's Rip Curl Pro at Bells Beach.

"During my heat at Bells, I ended up injuring my meniscus (cartilage in my knee)," Robinson said on Sunday in an Instagram post.

"After reviewing with a few specialists, and discussions with my team, I'll be pulling out of the Margaret River Pro.

"As you all know, Margs is my home break, and I'm always looking forward to being in @westernaustralia.

"Unfortunately, I won't be able to compete at Margs, but it's what's best for my recovery and long term goals.

"Next week I'll be starting physiotherapy.

I'm confident I'll be back for the next event. It's a long year and we are just starting!"

Robinson sits just behind Brazilian Joao Chianca in second spot on the World Surf League rankings.

The Australian will be replaced in the main draw at Margaret River by the second-placed finisher in the trials.

The window for the Margaret River Pro is April 20-30.