Chris Vermeulen will attempt to compete in the second round of the World Superbike Championship at Portimao, despite admitting he would need two months to regain full fitness.

The Australian suffered five torn ligaments, cartilage and muscle in the knee following a high-speed accident during the Phillip Island season opener, which he says would normally take approximately two months to fully heal.

However, doctors have since confirmed Vermeulen will not require surgery, while the on-site Clinica Mobile has given the Kawasaki rider the 'OK' to go racing this weekend too.

"The doctors at the Clinica Mobile have already said it is OK for me to race. On Sunday it is going to be four weeks since the accident and really I need two months for everything to heal properly.

"I sat on the bike for the first time and it is a little difficult to get my knee into position, but we can lower the foot-peg and raise the seat, do whatever we can to help that. The Clinica Mobile will tape up my knee and give me some injections for the pain.

"I am going out for practice on Friday morning to see what I can do. I am sure it is going to be possible to ride."

Vermeulen is one of just four riders on the grid not to have raced at Portimao before, along with James Toseland, Roger Lee Hayden and Sheridan Morais.