Cooper Cronk, Cameron Smith and Billy Slater after Melbourne's grand final win in 2012.

The Melbourne Storm's "Big-Three" era will officially be over at the end of the season after Cooper Cronk announced he was leaving the club after 2017.

Together, the Storm championship trio of Cronk, Cameron Smith and Billy Slater achieved plenty of success in Melbourne including their 2012 premiership and six grand final appearances.

The three all sit among the top 10 players for most wins in rugby league history and Cronk acknowledged the deep personal bond they share from before their days in Melbourne. 

"We haven't just played first-grade together, we played under-19s at Brisbane Norths since 2001," Cronk said. "I used to stay at Billy's house and live the dream to try and play professional football together, and here we are together.

"Cameron Smith used to pick me up in his Holden car and drive me across the bridge in Brisbane to go to Brisbane." 

Melbourne coach Craig Bellamy joked that things hadn't changed with Smith still providing Cronk with lifts to Storm trainings to this day.

 


In 15 seasons with the Storm, Cronk established himself as a superstar halfback of the game, winning the 2012 Clive Churchill medal and two Dally M Player of the Year awards.

With his departure to leave a large void to fill at the club, the 33-year-old predicts continued success for Melbourne.

"Whoever does come in (as replacement halfback), I promise I'll give them the keys to the city and teach them everything I know because I want this club to be successful whether I'm here or not," Cronk said.

"While Cameron and Billy are here playing, the club's in great hands. They're the best at what they do and they give so much time to the players. 

"To even think there might be a gap when I leave, I don't buy it at all."

Cronk also shares a close relationship with Bellamy who was shocked when his master halfback told him he would be leaving, expecting another one of Cronk's "ear-bashings".

Bellamy acknowledged the impact of his departure and the breaking of the Big Three.

"Cooper's downplaying it, he's going to be a very hard guy to replace," Bellamy said. 

"He's been a wonderful contributor to our footy team on and off the field for a long period of time. To replace that isn't going to be easy.

"It had to come to an end at some stage but when it does, it still doesn't make it easy.

"We've got a year to go and I know we're going to put it all in and he's going to put it all in."

Although it's not the fairytale finish many fans hoped for the legendary trio, it was a personal decision Cronk made for the sake of his fiancée Tara Rushton and himself.

"Selfishly, the four of us including Craig would like to finish at the same time and ride off into the sunset," Cronk said. "Unfortunately that's not the case."