In-form Roosters fullback James Tedesco admits it was a struggle to find his place in a new team at the start of the year but a focus on supporting through the middle of the ruck triggered his explosive Origin campaign and late-season form surge.

The Roosters spent big in an effort to capitalise on their premiership window, signing Storm, Maroons and Kangaroos veteran Cooper Cronk in place of Mitchell Pearce and luring Tedesco from the Wests Tigers.

It is hard to win a premiership without an elite fullback (Ben Barba, Billy Slater, Lachlan Coote, Greg Inglis and Anthony Minichiello are the past five premiership-winning No.1s).

Since the retirement of Minichiello and departure of Roger Tuivasa-Sheck the Roosters have got by with a combination of veteran Michael Gordon and a rotating cast including Connor Watson, Blake Ferguson and Latrell Mitchell (who is a far better centre now than he was a fullback in 2016).

The recruitment of Tedesco ensured star billing in the key spot but his stint started sluggishly; the team opened with a 4-4 record and a lack of cohesion among the play-makers – also including Luke Keary and Jake Friend – was becoming a growing concern.

Speaking to NRL.com in the lead-up to the blockbuster preliminary final against old rivals South Sydney in what will be the last match at Allianz Stadium, he admitted to struggling early but a focus on his defence and supporting the ruck had turned things around.

"Coming into this team it was hard to find my role and what I was best at," he said.

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"It's obviously a different side to what we had at the Tigers. Those first six to eight rounds I was still trying to find my feet and what was best for me and the team.

"After that Origin period I found my strength was around the ruck and with our powerful ball runners that's when I can find a lot of space and run the ball well and it felt like that's just natural now, whenever the boys are taking it forward I'm supporting and getting off the back of them.

"That's when I think we're playing our best footy as a team and obviously the combinations with Cooper and Keary and Friendy, that's just spending time with them all and practising at training."

A rejig of the side's attacking plans during the representative round break after a 24-8 Anzac Day loss to the Dragons was the catalyst for a form spike that helped Tedesco fend off a challenge from Manly custodian and eventual Blues winger Tom Trbojevic for the sky blue No.1 jersey.

Tedesco produced one of Origin's great individual performances in a dominant game-one win and was unlucky not to receive the player of the series award after starring in all three games.

He said the series boosted his confidence through the second half of the season and those performances, like his recent club form, were based on capitalising on space through the middle.

"Playing good footy at that elite level obviously brings a bit of self confidence but I just found my way here at the Roosters, it took its time," he said.

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"Even through Origin I was through the middle and that's when I was playing my best footy as well."

Tedesco does not believe he's a significantly different player in attack now to what he was at the Tigers, rather he simply has a different role. It is his work off the ball where Tedesco feels he has genuinely improved as a player.

"Defensively I'm definitely better," he said, crediting the teaching of coach Trent Robinson and Minichiello. Minichiello is not only the club's most recent premiership-winning fullback and a Roosters legend, he is also a former Italy World Cup teammate of Tedesco.

"Defensive line organisation and talk and getting across the back has definitely been an improvement because Robbo puts a bit of emphasis on that which definitely helps my game and the team," Tedesco added.

"Attack-wise, I don't think much has changed as a player. At the Tigers, we had a different team. At the Roosters I've had to play a different role.

"I'm running more metres here and supporting our boys a lot more. I'm trying to develop all areas and become a complete player."

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The stats bear out Tedesco's suggestion that his running has increased; he averages 193 metres gained per match which is easily the best of his career. That's up from 175 at the Tigers last year and his previous season-best of 152 in 2015.

The retirement of Billy Slater and cheekbone surgery for Trbojevic look to have reduced the race for the green and gold for the two end-of-season Tests against New Zealand and Tonga to just Tedesco and in-form Sharks custodian Valentine Holmes.

Greg Inglis is playing centre, Kalyn Ponga is out of contention after finishing the season early due to injury and Darius Boyd has also retired from rep footy.

"I haven't been trying to think about it too much," Tedesco said of a possible Test debut.

"I know if I'm playing good footy in the finals and for the Roosters that opportunity will come and I'm hoping I do play well and it does come.

"If I do play well and it does come it will be a dream to play for I haven't wanted to think about it too much because I know if I do that I'll go off my game."

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