Port Adelaide chief executive Keith Thomas has revealed John McCarthy was in contact with another team-mate shortly before he died.

McCarthy, along with several other Port players, was on an end-of-season trip in Las Vegas when he separated from team-mates at the Wynn Resort and Casino and walked roughly four kilometres alone to the Flamingo Hotel and Casino where he fell to his death.

It was during that walk that McCarthy phoned partner Dani Smarrelli in Adelaide in a confused and disorientated state, who in turn alerted one of the Power players in Vegas.

That said Power player spoke to McCarthy only moments before the fatal accident and was of the understanding that the 22-year-old was on his way back to the Hard Rock Hotel and Casino where the Port Adelaide group was staying.

Speaking on Wednesday, Thomas gave further details regarding McCarthy's final phone calls to his partner and the unknown Port player.

"I've spoken to Dani about it and while she was concerned John was on his own, seemed a little disorientated and perhaps lost, she was comfortable with the call and felt as if it went okay," Thomas said.

"It was a 'missing you' sort of phone call, but it is a private matter between them.

"She was however concerned enough, because he was on his own, to make contact with one of the other players … to try and get him back with the group.

"That player made contact with John who suggested he was on his way back to the hotel.

"At that point the group felt as if he was okay and that he was coming back.

"We would suggest the accident happened soon thereafter."

While it remained a mystery as to why McCarthy went to the Flamingo, Thomas said he had been briefed by those with the Victorian on the trip to explain why he found himself alone in the gambling capital of the world.

Thomas confirmed drinking had played a part in McCarthy's death with the Power players being present at XS nightclub at the Wynn hotel prior to the incident, but ruled out drugs following discussions with the group.

The 51-year-old also said he would not be admitting any club-based drug tests to dispel any suggestions otherwise with the players' welfare paramount at a sensitive time.

"The players went to check into their hotel rooms (at the Hard Rock) but they weren’t ready so they decided to head out and came across a club (at the Wynn)," Thomas said.

"They spent an hour in the queue … some got in, some didn't … some ended up in one section of casino, some in another … they spent the night in small groups.

"Throughout the course of the late evening they started to peel off and go to bed while others stayed at the casino. It would appear at this point John left the casino.

"The first time the group became aware of this was when Dani rung the player (who spoke to McCarthy) … and was giving every indication he was okay and that he was on his way back.

"The next point of contact that these guys had, having gone to bed, was in the afternoon when I rang them asking if they were all there, which was quite distressing."

There are no images of McCarthy on the roof where his fall occurred, but CCTV footage has shown the former Collingwood midfielder entering the Flamingo.

Thomas, who has not seen the footage himself, said McCarthy had been described as appearing a 'little drunk', as he walked up to the hotel.

McCarthy then took a lift before walking through a fire escape exit onto an adjoining mezzanine roof.

"Every indication at this stage is that the death of John was in fact a tragic accident," Thomas said.

"We can only speculate really as to why he wasn’t able to get back off the roof, but it appeared he felt as if he couldn’t find his way back and attempted to scale across to a palm tree where he fell.

"Suicide has been ruled out to the best of my knowledge by the coroner based on the investigation of John's body and the circumstances, and the tone of the conversations that were had in the immediate period before that."

The Port players who were present on the trip with McCarthy including recently re-signed star on-baller Travis Boak, veteran Brett Ebert and young gun Hamish Hartlett returned home to Australia on Wednesday morning.

Thomas said they would not make any public comment on the matter and would be provided with intensive grief counselling.