Two young Irishmen from Donegal are on trial for murder in Sydney, Australia, after allegedly beating a 66-year-old man to the brink of death outside their apartment in December 2018.

The trial of roommates Nathan Kelly, 23, and Christopher McLaughlin, 25, began in the Supreme Court on Tuesday, reports

Crown prosecutor Tony McCarthy told the court how the two young men spent the afternoon drinking by the pool of their apartment complex on Grosvenor Cres and Liverpool Rd in the inner-west suburb of Summer Hill. The men then spent the night boozing before returning home and fatally assaulting Paul Tavelardis just after midnight on December 29, 2018.

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Tavelardis, an Indigenous man and a grandfather of nine, was battling leukemia at the time of the attack.

Tavelardis, suffering from critical head injuries caused by blunt force trauma, died in the hospital a few days after the alleged attack .

Kelly and McLaughlin, both construction workers, moved to Sydney on working visas in May 2018. They have pleaded not guilty to murder and will argue they never intended to kill Tavelardis, reports Highland Radio.

Witnesses who saw the young men that afternoon and evening said they were “very drunk.” According to the prosecutor, Kelly and McLaughlin were later seen on CCTV falling down the stairs in an underpass below a railway station due to intoxication.

Kelly had told police that he and McLaughlin confronted Tavelardis after they saw him trying to break into McLaughlin’s vehicle. Kelly claimed the man approached them “shouting and roaring” armed with a metal pipe.

According to the prosecutor, a police examination of McLaughlin’s vehicle found no evidence of damage.

Two young Irish men have faced court charged with murder. 21-year-old Nathan Kelly and 24-year-old Christopher McLaughlin are accused of bashing a 66-year-old man. Paul Tavelardis was found on a street corner in Summer Hill late last month. He died later in hospital. #7News

— 7NEWS Sydney (@7NewsSydney) January 9, 2019

Tavelardis’ son Bradley has previously said he believes his father had gone “walkabout” and may have been sleeping in his car at the time of the attack.

“He loved to travel, that was his indigenous side, he loved to go, as we say, ‘walkabout.’

“Every two or three years he would save enough money, buy a sedan and go out into the desert and sleep in the back of his car.”

McCarthy said several eye witnesses would attest to seeing the two men chase and attack Tavelardis, who was repeatedly kicked and punched after being knocked to the ground.

Tavelardis was “barely conscious” and bleeding from the head, mouth, and nose by the time police arrived about 10 minutes after the attack. It appeared he had also vomited and soiled himself.

One witness has claimed he heard the victim cry out “Why are you doing this to me?” during the attack.

A scan taken at Royal Prince Alfred hospital showed bleeding in the lining of his brain. He never woke up from surgery  and died after his family decided to turn off his life support.

Kelly’s barrister David Campbell, SC, told the court his client “vehemently denied” assaulting Tavelardis after he fell to the ground.

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McLaughlin’s barrister Margaret Cunneen, SC, said her client never intended to kill the elderly man. 

"A threat emerged from the dark and in reacting to that threat there was no intent to inflict grievous bodily harm on that man," she said.

The trial continues.