The 35-year-old said he was planning to go out on a high by helping the Sydney Roosters, the club he joined for his swansong last season, become the first team to win back-to-back National Rugby League (NRL) titles in a quarter of a century.
Twice a winner of the Dally M medal as the "best and fairest" player in the NRL and World Player of the Year in 2016, Cronk played 22 times for Queensland in State of Origin and 38 times for his country.
Along with Billy Slater and Cameron Smith, Cronk was at the heart of a Melbourne Storm side that won four NRL titles, a Queensland team that won State of Origin seven times in eight years and a Kangaroos squad that won two World Cups.
Although two of the NRL titles were later stripped from the Storm for salary cap breaches, the trio will all almost certainly end up joining the select group of Australian players dubbed rugby league "Immortals".
Fullback Slater retired at the end of last season but hooker Smith is still playing with the Storm and Cronk, who quit representative rugby after the 2017 World Cup final, had a special word for his two former team mates.
"Billy and Cameron, I don't think 'thanks' cuts it," he told a news conference in Sydney.
"Those two guys will go down in history as the two best players in their positions for as long as the game of rugby league is around.
"So that probably makes me the best third wheel the game has ever seen because too, because I just jumped on the back of whatever they were doing."
Cronk, renowned for his professionalism, also heaped praise on the "inspirational" Craig Bellamy, the coach who built a dynasty in Melbourne with the help of his talent.
While Bellamy was the tactical brains off the field, Cronk was the general on it, orchestrating the attack with his quick hands and freakish ability to get the ball to do his bidding off the foot.
He showcased his courage by winning a fifth NRL final with the Roosters against the Storm last year despite having a fractured scapula, included in the side for his leadership and on-field coaching nous.
Cronk reassured his team mates at the eastern Sydney club that announcing his retirement would by no means reduce his commitment to their championship charge.
"I tell you what, if anyone thought I worked hard for the past 15 years," he said. "Well, come watch me train Monday to Friday for the next 20 weeks."
(Reporting by Nick Mulvenney, editing by Greg Stutchbury)
