JOHN McCarthy was a talented footballer who had yet to offer his best to the AFL.

But as his family, friends, teammates and indeed the entire community struggled to accept his death on Monday, by far the most saddening reality was that they had lost a really decent, genuine young man.

As tributes from his former teammates, opposition clubs and players and his two AFL clubs Port Adelaide and Collingwood flooded in, it was perfectly clear McCarthy was loved by all who knew him.

Leave your tribute to J-Mac here

Power CEO Keith Thomas choked back tears when he described the 22-year-old as a "popular young fella".

"John was a very popular Port Adelaide player and had embraced the club as we had embraced him," Thomas said.

"There were tears (when the players and staff were informed of his death), he's a popular young fella.

"It's devastating news … he's a fantastic young fella, well liked … it's so disappointing on a football front, but more on a personal front."

McCarthy attended last Friday night's John Cahill Medal count at Adelaide's Entertainment Centre, where he was interviewed on the red carpet with his long-term girlfriend Dani Smarrelli by teammate Matt Thomas.

A grinning McCarthy described Smarelli as "beautiful" and claimed the 24-year-old singer "took a lot longer than me (to get ready)".

Smarelli countered by telling Thomas that her man had still been doing his hair on the way to the best and fairest function.

As news filtered through early on Monday morning of McCarthy's tragic death, the Power's football manager Peter Rohde left for the United States to be with the 10 players still in Las Vegas.

Those who remained in Adelaide convened at the club's Alan Scott Headquarters to be told their mate was gone; their faces told the story.

Troy Chaplin, Danyle Pearce, David Rodan, Daniel Stewart and Cameron Hitchcock were amongst them. Several appeared overcome with emotion. The rest solemnly left Alberton Oval with their heads bowed.

The club vowed it would get through the traumatic time, but described it as a devastating emotional blow.

Collingwood confirmed it would wear black armbands in its semi final on Saturday night against West Coast at the MCG.

The club's captain, Nick Maxwell, said the Magpies had lost a "great friend".

“It’s a terrible day, a devastating day. Everyone here, especially his closest friends, feel for the McCarthy family. Our thoughts and deepest sympathies are with them as we all bind together during this time. Today we lost a great friend," he said.

But perhaps the Power's recently named club champion Kane Cornes put it best, when he tweeted this tribute:
 
"Hug your kids and tell your family you love them. We've just lost the nicest guy and best teammate you could ever ask for. Too sad".