Rugby league coach Josh Hannay has described the industry as "brutal" while reflecting on the sudden death of his "friend and mentor" Paul Green.
Police said Green, 49, died by suicide on Thursday morning.
"I've spent the last 12 hours or so trying to comprehend what's happened, why it's happened," Hannay told ABC Radio Brisbane on Friday morning.
"This industry we're in, right, it's a brutal industry.
"I know that on a professional level, the last few years have been really challenging for Greenie, given what happened at the Cowboys and with Queensland."
Green left the Cowboys midway through the 2020 season after recording three wins from the first 10 games, with Hannay stepping in as interim coach.
Last year Green coached Queensland in the State of Origin and stepped down after the Maroons lost the series.
Hannay said the industry was either "lifting you up or tearing you down".
"The highs are the highest of highs and the lows are the lowest of lows," he said.
Green was at the helm of the Cowboys when the team won its first premiership in 2015.
Hannay, who played with Green and later became his assistant coach, said he caught up with his "friend and mentor" at a Cronulla Sharks reunion in Sydney on Saturday.
"It was great to see Greenie. I hadn't seen him in about a year," Hannay said.
"It was always good fun having a beer with Greenie. Life of the party. Plenty of good stories.
"I feel really fortunate now, given the circumstances, that I got to have that time with Greenie on Saturday night."
Hannay said Green loved the song It's Five O'Clock Somewhere by Alan Jackson and Jimmy Buffett.
"I can hear him now singing it. It didn't matter where you were, he'd find some way to get that song over the speakers," Hannay said.
"I'll be playing that song at some point today."
A minute's silence will be held across all NRL games this round to remember Green.
John Cartwright, who was an assistant coach to Green when the Cowboys won the 2015 tournament, said Green had given him a second chance at coaching.
"I was not in the best place myself at the time," Cartwright told the ABC's News Breakfast program.
"[I was] coming to the end of my coaching career at the Titans and was a little bit lost.
"And [I received] a call out of the blue — Greenie asked me to come up there and join the Cowboys.
"Initially I just sort of said, 'Mate I wasn't in the right frame of mind. I wouldn't be able to give you any sort of help,' and he said, 'Look, have the off-season to think about it and I'll give you a call in January,' and he did.
"I'm so glad that I took the opportunity that he gave me to go up there and help out."
Kevin Walters, the coach Cartwright is currently serving under in Brisbane, said the Broncos had already had a team discussion about mental health this morning.
"I think it's important that we check on each other each day, particularly with the mental health side of things, and it's something that I believe the NRL need to put more focus on," Walters said.
"Our players, our coaches, our support staff, everyone involved in the game, we need to make sure there's someone there for you."
