Butler, 20,  relocated to Mackay, north Queensland, in January to prepare for his first season with the Cutters after a year with the Burleigh Bears on Queensland's Gold Coast. He was a former Melbourne Storm youth player.

Aldridge said Butler's family and the Cutters community were still in shock after the youngster's death.

"We met as a group at midday on Monday and while nothing prepares you for these situations, the players and support staff are united in their wishes for Hayden's family," he said.

"This is an extremely difficult time for the Mackay Cutters as a club and also our players that formed a close bond with Hayden during his short time in Mackay.

"Our thoughts and prayers remain with his family during this difficult period."

Butler had played under current Cutters coach Kim Williams at the Storm and Aldridge said he had quickly established bonds with the playing group.

"Hayden was a natural leader who had made an immediate impact at the Cutters with his friendly nature and determined attitude," he said.

"He had many close friends at the club who had played with him throughout his junior career and were looking forward to playing alongside him again in 2015."

Butler was one of two rising rugby league stars who died suddenly over the Australia Day long weekend, leaving the rugby league community in shock this week.

North Queensland Cowboys Under-20s player Regan Grieve died just four days shy of his 19th birthday, cutting short his life and promising rugby league career.

The Cowboys youth player was an Australian Schoolboy and Queensland U18 representative, whose development as a forward was putting him in the frame for an NRL debut.

Two of the NRL's welfare education staff are in Mackay and local organisations have offered their support to  players and friends of Butler.

The deaths come almost two years after former Cowboys squad member and Cutters player Alex Elisala took his own life.

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