The 22-year-old, who clarified it was his hand, not his wrist that was injured, confirmed he was involved in an altercation outside Hillarys nightspot Bar 120 on Saturday.
The dual Breckler medallist said he did not intend to report the matter to police and did not know the person involved in the incident.
“It was spontaneous… just waiting out the front and things escalated from there,” he said. “I’m not going to comment on anything else… it was an unprovoked attack and didn’t end well for me.”
He described coach Bill Monaghan as “not happy about it”.
“I’m really disappointed, I was obviously looking forward to a big year,” he said. “It’s frustrating, (but) I’ve just got to look forward to the middle of the year.”
With his hand in a cast, he said he would be kept to cardio work while he waited for the injury to heal.
It is expected to keep him out of action for two months.
West Perth plays its final pre-season game against Perth on Saturday before its 2016 WAFL campaign begins against South Fremantle on March 19.