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"And when the football's out, he just naturally does what he does. He's been great this off-season and I'm sure he's excited as anyone else to get onto the field."With the Eels' season-opener one month away, Mannah insists Hayne is a far different player from the one who made a dramatic exit from the NRL in 2014.
Hayne has since appeared in the NFL and attempted to feature for Fijian sevens team at the Rio Olympics before struggling in his NRL return at the Gold Coast.
He's also become a father for the first time and has been the subject of a rape allegation in a civil suit stemming from his time with the San Francisco 49ers in 2015, which he says he will vigorously defend.
"I feel there's a bit more maturity about him," Mannah said.
"He's starting to grow off the field and he's obviously had some life lessons that he's gone through and come back a bit more of a complete player, which is good for us as a club.
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"And he's got a lot of leadership qualities as well, which really helps myself and a few other senior players leading this team."
But Mannah also says the major difference between Hayne now and the one who claimed the Dally M medal alongside Johnathan Thurston in 2014 is the make-up of the Eels.
Hayne was widely seen as a one-man band before his departure from the NRL club.
"There was a lot of pressure on him in the past when he used to play for the club. It was a case of, if Jarryd plays, we're a much bigger chance of winning the game," he said.
"Now we've developed a team. (Coach Brad Arthur) and his staff have done a great job to develop a team that doesn't need just one player."
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- AAP