Jarryd Hayne says he is "devastated" after going back on a promise to rejoin boyhood club Parramatta Eels.
The 28-year-old has instead joined their NRL rivals Gold Coast Titans on his return to rugby league, in deal reportedly worth up to £1.37m - the biggest in the competition's history.
Hayne said he would only return to the NRL to play for the Eels when he quit in 2014 to play American football.
"I'm saddened it had to end like this with the Eels," he said.
Having played American football in the NFL for the San Francisco 49ers in 2015, Hayne was unsuccessful in an attempt to secure a place in Fiji's rugby sevens team for the Rio Olympics.
He then held discussions with the Australian Rugby Union over a move to Super Rugby, before deciding to return to the NRL.
The former Australia international claims the Eels did not make a formal offer.
However, the club insisted it had but, in a statement, added their offer "was not comparable to the other proposals".
Hayne's two-year deal with the Titans is worth a reported AUS$1.2m (£680,000) a season.
"I'm truly sorry for disappointing all the Parramatta fans, players and the club that have been with me from the start," said Hayne, who played for the Eels from 2006 to 2014, scoring 103 tries in 176 appearances.
"This has been a difficult decision for me and I'm as devastated as any fan that I won't be pulling on the blue and gold jersey this year."
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