Despite first aid at the scene, she died at St Vincent’s Hospital hours later.
Investigators do not believe a weapon was used in the alleged attack.
A bloodied, injured and handcuffed Barker was taken away from the home by police, who have since charged the 74-year-old with murder.
The former civil engineer had “admitted” to both police at the scene and in a formal interview, Waverley Local Court heard on Friday.
The alleged murder was also witnessed by a person who has given police a “profound” statement, police prosecutor Sergeant Nicole McMahon said, calling the case against Barker “overwhelming”.
“There are serious allegations of significant violence displayed by the accused which caused the death of his wife,” McMahon said.
Barker’s lawyer Matthew Bogunovich told the court that the alleged murder “appears to come as a result of an unraveling of the relationship at home”.
In an unsuccessful bid for bail, Bogunovich told the court that Barker had never been charged with an offense or subject to an AVO and had “not only a long marriage to the victim but had a very long career as a civil engineer”.
Barker’s age and the nature of his alleged crime would make him “vulnerable” in prison, he said.
Remanding Barker in custody, Judge Clare Farnan said the allegations against Barker were “clearly unusually serious” and, if found guilty, it would be “inevitable” he would serve a long prison sentence.
After a night in the cells at Waverley police station, Barker will be taken to Silverwater’s Metropolitan Reception and Remand Center where he is likely to be placed in protective custody until his next court appearance.
According to his LinkedIn profile, Barker works for telecommunications company Schokman in western Sydney.
“It has been a great pleasure to work for Schokman Pty Limited, where I prepared tenders and advised on business processes,” reads his profile.
A representative for Schokman said: “Barker has not worked for the company since 2019, when he was a part-time consultant for a short time.”
For most of Friday, the home remained a crime scene as detectives collected evidence inside the property and in a black Mazda parked in the couple’s driveway.
A bunch of pink flowers wrapped in plastic were leaning on the couple’s driveway Friday afternoon, as neighbor Sarah Littman told reporters she was in “pure shock.”
“You don’t expect to see this on your morning commute, it’s just so sad. I’m a bit speechless to be honest,” she said.
“You don’t really think these things can happen, especially not so close to home.”
Support is available from the National Sexual Assault, Domestic and Family Violence Advice Service on 1800 RESPECT (1800 737 732).
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