The 25-year-old apologised via video link to a charge he previously denied.
The court heard that De Goey will be required to attend 10 therapy sessions that focus on alcohol and anger management.
De Goey’s lawyer Jacob Kaplan said the 10 sessions are “fairly standard in these sort of cases”.
“Once that’s done, we write a letter to the court from the therapist showing that’s been done, and the case is over,” he said.
The Collingwood player originally faced four charges, including assault with intent to cause injury.
However, those charges were downgraded to second-degree harassment.
The other three charges were dropped.
Mr Kaplan said footage from the nightclub led to the assault charges being dropped.
“It showed what the victim said happened didn’t really happen,” Mr Kaplan said.
“That’s the important thing which is why I think we were able to get this case reduced.”
De Goey had previously been stood down with pay by Collingwood after the original charges were laid.
Collingwood reinstated him to the AFL program last week.