Star Penrith halfback Nathan Cleary says it took just 20 minutes of game action for him to know that James Maloney is a five-eighth that he will gel with this year.

The 20-year-old son of Wests Tigers coach Ivan has been a sensation in his 41 career games over the past two seasons, winning almost 60 percent of his games and scoring 346 points (14 tries and 145 goals at 86%).

It's even more remarkable when you consider that outside of his NRL debut alongside veteran Jamie Soward, Cleary has never had an established five-eighth alongside him and he's had to shoulder the bulk of both the game plan and playmaking duties.

Much of his career to date has been played with utility back-rower Bryce Cartwright next to him in the No.6 jersey. Fellow rookie Te Maire Martin (now at North Queensland) and Matt Moylan (now at Cronulla) also spent game time with Cleary in the halves.

Cleary said while having a veteran half alongside him shouldn't change his own game too much, he welcomed having an older head to bounce ideas off and someone who provided a calming influence over the team.

"We only got 20 minutes together on the weekend [in the trial win over the Roosters] but it felt natural," Cleary told NRL.com at the 2018 launch of Fox League on Tuesday morning.

"It felt like we had played together before which was good, and I'm looking forward to finally getting into the swing of things and playing 80 minutes together hopefully this weekend leading into round one.

"It definitely helps having someone like Jimmy who's so successful and he's a great player. To have him alongside me, it's really good and I think my role as a halfback doesn't change too much, I'm still directing the team around but it's good having him there to take a bit of the pressure off and I'm really lucky to have him there."

Cleary said he had already learned plenty from the man who has played for both NSW and Australia as well as winning two Telstra Premierships.

"We've only played 20 minutes together but even on the weekend, he's just so calm in everything he's doing and that kind of reflected on the way we were playing, everyone else was really calm and no-one was too frantic. Even at training, he brings that same attitude and he's really good to have around."

Of the trial in general, Cleary said the club was broadly pleased with the performance given some mostly solid defence and a low error rate.

Penrith Panthers halfback Nathan Cleary
Penrith Panthers halfback Nathan Cleary ©Scott Davis / NRL Photos

"It was nothing too special, but everyone kind of did their job," he said.

"As a whole, everyone was pretty happy with how it went. We've definitely got some areas to work on but we know how to get rid of those now."

Utility Tyrone Peachey mostly played at centre against the Roosters despite Bryce Cartwright's off-season departure to the Gold Coast slightly easing the club's back-row log-jam. He finished off a nice try started by Cleary but was also burned by Roosters centre Joey Manu for a try.

"Peach has been training the whole off-season at centre, mainly because Waqa Blake had shoulder surgery so we'll see how that goes but I think it's a luxury to have with all this competition for spots in the team," Cleary added.

Cleary expected a close to full-strength line-up to face the Bulldogs at Belmore on Saturday as the team looks to fine-tune for their season-opener against the Eels at Panthers Stadium.

"Yeah, I think we should be just about full strength. Hopefully, we get away with no injuries this weekend and we're pretty much full strength for round one," he said.

"We need to get off a better start than we did last year."