Roosters forward Aidan Guerra is still benefiting from the legacy left at the club by Sonny Bill Williams.

Sonny Bill Williams was formidable for the Roosters in his two years at the club but his teammates say his influence over the squad is continuing to reap dividends even after his departure to rugby.

One such beneficiary is Roosters forward Aidan Guerra, who will be effectively replacing his former teammate on the Tricolours' right edge when his side travels to Townsville to face the highly-fancied Cowboys on Saturday.

"You learn something from every player you play with, play against or whoever you're coached by – they have an influence on your career so obviously we have taken things from Sonny within this squad," Guerra said.

"Everyone in the squad has worked on themselves the past couple of years and there was always an influence there from Sonny. We've put in the hard yards over the pre-season and we're hoping that, in conjunction with our work ethic and our lives away from football, will build towards a strong season."

Martin Kennedy, back at Bondi where he played alongside Williams in 2013 before a short-lived stint in Brisbane, said it was a case of Williams pushing the team to always better themselves – a legacy which still remains.

"He's such a professional and champion trainer, so much so that you feel like a bad person if you don't add to the team the same level that he did. If you're not doing the extras or doing your rehab to a tee or trying to better yourself to the level that he did then you feel like you're not contributing," Kennedy said.

"He's a phenomenal player and he's constantly strived to better himself. He raised the bar here and everyone has picked up since then. I knew coming back to the club this year everyone would be better off from him being here.

"The boys have all challenged themselves to try and continue on what he's started."

Kennedy added 2015 will be a season when "everyone will be taking a leaf out of Sonny's book".

Sydney Roosters 2015 season preview