The arrival of Luke Keary in the off-season has already had a profound impact on the Sydney Roosters, as the Tricolours sit pretty with two wins from as many starts in 2017.

And while the new recruit is attracting all the plaudits, it's the form of one of the men that he replaced in the halves that has caught the eye of keen observers at the club. 

Ryan Matterson knew he had to reinvent himself once news broke that Keary had joined the club, and following a pre-season chat with Roosters coach Trent Robinson, he decided to do something about it.  

Matterson started his rugby league career in the outside backs but moved to the halves as a 15-year-old. He went on to captain Parramatta's NYC side in 2014, taking them to the preliminary final in a year that also saw him represent the Junior Blues and Junior Kangaroos. 

He made his NRL debut last year at five-eighth in the Anzac Day clash against the Dragons and went on to play 15 games for the Roosters, splitting his time between the halves and the interchange bench before shifting to the back row in Round 26. 

The 80-minute hit-out against the Broncos at the end of 2016 was the catalyst for his permanent switch to the forwards, with Matterson fully aware that he would struggle to compete for a playmaking role with Keary and Connor Watson ahead of him in the pecking order. 

"I knew Luke Keary was coming to the club so I spoke to Robbo about changing my role," Matterson told NRL.com following his side's 28-24 win over the Bulldogs in Round 2 of the Telstra Premiership. 

"I wanted to be more physical and I wanted to play back row, although tonight I seemed to play everywhere but second row. It doesn't worry me at all where I play. I don't even train in the middle. I just play there on the weekends.

"My dad tells me all the time 'If you play football then you're a footballer, no matter what position you play'. My dad's my harshest critic and he just wants me to run hard and tackle harder."

Size has never been an issue for the 22-year-old, and at 194cm, some thought he was too tall to play in the halves anyway. 

Now he looks at home in the middle having added the bulk necessary to match it with the likes of Bulldogs big men David Klemmer and Sam Kasiano on a weekly basis. 

A rigorous off-season regime of four training sessions a week coupled with a hearty diet have seen him put on seven kilos since last year and the results are showing on the field with Matterson helping his side take out the Downer Auckland Nines in February and getting them off to a flying start in the NRL. 

"I finished last season at 101 kilos, but now I'm nearly 108. It's a big difference and I feel it out there. I get tired a lot quicker but I feel like I can mix it with the big boys," he said. 

"I try to eat 500 or 600 grams of meat a day. I'll probably have two plates of dinner, a plate of veggies and a plate of rice, and I try to eat five times a day.  

"I've always been a big eater, but the biggest difference for me is what I did in the off-season. I just kept training and doing weights and it's definitely paying off. My next goal is to secure a starting spot."

Matterson's newfound versatility was on show against the Bulldogs with the 22-year-old forced to fill a number of positions to accommodate his side's mounting injury toll. 

He finished the game with 144 metres and a piercing line break off the bench in a performance made more remarkable by the fact he didn't even line up in his preferred position. 

"He didn't actually play back row tonight, but he played lock, a bit of front row and centre. I thought he played really well tonight," coach Robinson said after the Bulldogs game. 

"The role that he played in that game was big for us. We lost Kane Evans in the warm up so he had to go in the middle and he carried the ball strongly. He and Zane Tetevano carried the ball through the middle during that period really strongly for us, and then he ended up out at centre having to make edge decisions and he did it well. 

"He's been great since he came on for us. He's played so many different positions for us and he's happy to."

This article first appeared on NRL.COM