Max Gawn is "devastated" about Angus Brayshaw's sudden AFL retirement, saying it leaves massive holes at Melbourne on and off the field.
Amid fierce ongoing debate about concussion, Gawn has also backed the league's support for Brayshaw.
Collingwood captain Darcy Moore, who came through in the same 2014 draft as Brayshaw, says the concussion issue is complicated and has no easy solution.
Days after Brayshaw's shock announcement, concussion was the dominant issue on Monday as the 18 club captains had their annual pre-season media call.
The AFL also faces a class action from past players over health issues which they say stem from on-field concussions.
"As a die-hard Melbourne supporter, I am quite devastated about the fact that we're not going through with Angus Brayshaw this year," Gawn said.
"As a friend, I'm also very, very devastated in terms of what's happened.
"A tiny bit of a sense of relief, in terms of the concussion battles he's had, now (they're) no longer.
"But ... he's just signed a five-year contract, he's a premiership teammate, he's a very, very, very good friend, it's just been cut short a little bit earlier than I thought it would be."
Gawn added that Brayshaw would leave a yawning gap, for his on-field ability as well as the ability to generate spirit around the club.
"I'm not going to undersell that - that's a big loss for us, both on and off the field," he said.
Gawn said he and Brayshaw had plenty of conversations ahead of the announcement, with some tears and plenty of laughs.
"He's well. We've had a lot of conversations ... we've since had a nice bottle of Grange to talk about the premiership year and the 10 years of times we've had," Gawn said.
The Demons skipper was also adamant that the league had supported Brayshaw properly.
"I certainly know (as a close friend), Gus was well looked after, from first concussion to last concussion," he said.
"I'm sure Gus would stand here today and say he's had incredible support from the AFL."
Brayshaw's latest concussion was a high-profile incident in the qualifying final last year, when Collingwood defender Brayden Maynard cannoned into him.
"Brayden is similar to me ... you don't want to see a fellow player end their career like that," Moore said.
"Brayden expressed his regret and remorse at the time and he's pretty genuine about that."
Moore added that Brayshaw's news was heartbreaking.
"First things first, I really hope that his welfare and wellbeing ongoing are in a good place, that he doesn't experience symptoms and he lives a long and happy life.
"It's such a shame to see his career cut short like that.
"The issue of concussion is not going anyway any time soon. There are no obvious answers coming in the short-term.
"The best we can hope for as players is that the league is genuine about making the game as safe as it possibly can be ... I'm pretty confident that's the case."
Collingwood player Nathan Murphy announced this month he is not ready to resume full training as he also deals with concussion issues.
"He's made a really mature decision and a really professional decision," Moore said.
"We're really supportive of that, happy for him to take as much space as he needs to get himself in the right frame of mind."
Moore said coaches at Collingwood are being more deliberate around contract drills at training because of the concussion issue.