Port Adelaide football club has confirmed that player John McCarthy has died in Las Vegas.

The 22-year-old player was found on the driveway of the Flamingo Hotel about 5.40am local time.

Port Adelaide CEO Keith Thomas said McCarthy was holidaying with 10 teammates who left Australia last Saturday.

"My understanding is that he fell from a building," Thomas said.

McCarthy was not with his teammates when he died but Thomas understood witnesses were "on the ground at the incident".

More to come.