Finley Goodwin was denied bail when he appeared at Newtown Local Court on Wednesday, shaking his head as he learned he would spend nearly the next two months in custody.
The 22-year old was arrested on Tuesday afternoon, nearly a week after an off-duty officer was left unconscious on one of Sydney's most popular entertainment strips.
Emergency services were called to Enmore Rd in inner-city Newtown on January 22, when they treated two officers - including a 25-year-old who was unresponsive and being given CPR by an off-duty nurse.
The second officer, also aged 25, suffered facial injuries. Both men have since been released from care.
On Wednesday, the court was shown footage of a person on the ground with their head being stomped on as they were swarmed by a group of young men.
Koby Weaver, 20, is accused of seriously injuring the officer in the assault, while Danai Deneiderhavsein, 18, has also been charged with taking part in the group attack.
Goodwin allegedly king-hit one of the officers as the policeman tried to help his fallen colleague.
Prosecutors said Goodwin had long hair at the time of the incident, but it had since been cut shorter in an attempt to help him evade capture.
He has been charged with inflicting grievous bodily harm with intent and assault occasioning actual bodily harm in the company of others.
But Goodwin's father Jason said the accusations against the 22-year-old were completely out of character and he felt sick to hear his son would remain in custody.
"There's two sides to it, so we'll find out in court," he told reporters.
"He's only a young kid and (they're) two grown men who are off-duty and probably inebriated too."
Goodwin was not accused of being the instigator of the assault, but he also did little to restrain or deter his co-accused, the court was told.
Magistrate Alexander Mijovich said investigators believed the two off-duty officers approached Goodwin and the two other men as they argued with each other before the assault.
"This is serious offending, it's violent offending," he said.
"Mr Goodwin moves away a couple of times.
"At no stage does he prevent his colleagues from getting involved."
Deneiderhavsein and Weaver faced Downing Centre Local Court on Friday, when both were denied bail.
Weaver is charged with causing grievous bodily harm with intent, while Deneiderhavsein is facing two counts of assault occasioning actual bodily harm in company.
All three men are due to return to court on March 20.