Wickliffe punched the man in the face and he crawled across the lounge and dragged himself outside, where he sought help from a local service station.
The man suffered a fractured eye socket and bruising to his face, head and arms.
Ms Lawrence said police accepted the man had been asked to leave, refused and then pulled a knife on Wickliffe. She said the question was how reasonable Wickliffe's use of self defence was.
"The police therefore accept that there was a threat to Mr Wickliffe but nonetheless his reaction was disproportionate to that threat."
Defence lawyer James Elliot said Wickliffe had delivered a "series of punches" after being challenged with the knife.
"Mr Wickliffe was at his partner's home, an uninvited person has turned up ... Mr Wickliffe has confronted this person going in, has asked this person to leave and a knife has been presented."
Judge Peter Hobbs said Wickliffe had a long history of violence, dating back to the early 90s, and had a recent conviction for assault in 2012.
Judge Hobbs said Wickliffe's reaction was out of proportion to the threat.
He convicted him and sentenced him to 120 hours' community work and 9 months' supervision.
