Roosters forward Aidan Guerra doesn't need reminding how good his Maroons teammate Johnathan Thurston is.

Guerra on JT alert for Roosters

Aidan Guerra has experienced both sides of the coin when it comes to the effectiveness of Cowboys lynchpin Johnathan Thurston, which is why he knows he and his Roosters teammates will need all hands on deck when trying to contain the superstar on Saturday night.

Weeks before making his State of Origin debut alongside Thurston last season, Guerra was victim to a masterclass by the veteran playmaker when the Cowboys smashed the Roosters 42-10.

On top of that, even though the Roosters would end up eliminating North Queensland in last year's semi-final, Thurston ensured it went down to the wire after playing a huge part in turning a 30-0 deficit into 30-all scoreline, before a James Maloney field goal proved the difference. 

"That's what happens when you fall asleep on a guy like that and a side like that," Guerra said in relation to that match.

"They are very strong all over the park and I'd like to think we learned plenty of lessons from that semi-final. We have to play it through for the entire 80 minutes otherwise things will get a bit hairy."

Having trained with Thurston in Queensland Origin camp, Guerra knows as well as anyone how effective the 31-year-old can be.

"He has been on top of this game for the most part of 10 years now. I've noticed what everyone else has noticed – he won't stop until the hooter goes and he'll always be the one supporting and demanding the best out of his teammates and himself," Guerra said.

"Everyone is aware of JT's capabilities on the field so we just have to work on our system and have belief in it and have everyone putting in extra effort on top of that, because if you fall asleep for a second he's going to capitalise."

On the flip side, the Cowboys need to be wary of Guerra as he embraces the role left behind by Sonny Bill Williams.

A man on the mission in the Roosters final trial against the Sea Eagles, Guerra's performance suggests the 27-year-old is building towards a huge year – something the man himself is playing down.

"We only had one trial allocated for most of us players this year and it was just a matter of getting a measure of where we are at as a team and where we were as individuals," Guerra said. 

"Against Manly a lot of us felt we needed to put in extra effort across the field and I guess I was just one of those."