Port Adelaide has confirmed 22-year-old John McCarthy is the AFL footballer who has died in Las Vegas.

Power Chief Executive Officer Keith Thomas said McCarthy was holidaying in the United States with ten other Port players when the incident occurred.

"It is our understanding that at the time of his death, he wasn’t with any other Port Adelaide players," Mr Thomas said.

"The players who were holidaying with John are planning to return as soon as we can get them back."

He said the club did not have many details of the incident, other than that it happened at a different hotel to where the players were staying.

"My understanding is that he fell from a building, but I don’t have any more detail than that," Mr Thomas said.

A Facebook tribute page, R.I.P John McCarthy (19 November 1989-10 September 2012), was set up this morning and has already received tens of thousands of members.

John McCarthy played 21 games in his debut season with Port Adelaide this year after joining the club from Collingwood in the pre-season draft last year.

He was drafted by Collingwood in 2007, having played 18 games for the Magpies from 2008-2011.

Mr Thomas said the death was an enormous shock and a terrible tragedy for John’s family, partner and friends as well as for the club and the wider Port Adelaide community.

"John embraced Port Adelaide and we embraced him, and we are deeply shocked and saddened by his passing," Mr Thomas said.

"He was a very popular player among his team mates and our supporters.

"Our thoughts and prayers are with his parents and his family right now."

A statement on the club’s website says the McCarthy was traveling with Travis Boak, Matthew Broadbent, Alipate Carlile, Brett Ebert, Hamish Hartlett, Tom Logan, Andrew Moore, Paul Stewart, Jackson Trengove and Justin Westhoff.

AFL Chief Executive Officer Andrew Demetriou extended his condolences and said it is a tragic loss.

"This is a terrible tragedy for John’s loved ones and our deepest sympathies go out to them," Mr Demetriou said.

"It is a very sad day for the Port Adelaide Football Club and the rest of the AFL industry to lose a young man in the prime of his life."

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