Merrin played 250 NRL games included 151 for the Dragons, with stints at Penrith and in the UK Super League with Leeds.

He dropped off the Dragons' list of 21 for Sunday's Anzac Day showdown with the Roosters, with recruit Josh McGuire included instead.

Merrin came off the bench in the Dragons 32-6 triumph over the Roosters in the 2010 grand final, as well as going on to play 13 games for NSW and seven for Australia.

"I'm very happy to be able to finish my career on my own terms. This was a decision where I had to be true to myself. I have outgrown the game and the game has outgrown me, although my appreciation for rugby league will never die," Merrin said.

"My dream growing up was always to play for the Dragons, a club I have always held in high esteem. I have achieved everything my younger self ever wanted and that is something I'll always be grateful for.

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"The time I spent at the Penrith Panthers, another prestigious club I hold close to my heart, remains one of the proudest things I also had the pleasure of being part of.

"I wouldn't have been able to achieve everything I have without my family and the sacrifices they made. They, alongside my beautiful fiancé and baby boy, have been there throughout the highs and lows of my career.

"They also rode the wave of emotion when it came to this decision to conclude a wonderful career. I'm keen to see the younger players step up in my place as the Dragons continues its exciting journey."