"He punched me in the private parts and then the face," Stuff reported.
"I grabbed hold of him and said there's no need for that and obviously he took offence to that and held me down by the neck and started choking me. I was seeing stars at one point, it was real hard to breathe."
Lancaster said the game had carried on for three or four phases while Ilalio kept strangling him. The referee then noticed what was happening and blew his whistle, and a Prebbleton player tackled Ilalio to free Lancaster.
Ilalio was shown a red card, while Lancaster did not play on for much longer because he had difficulty breathing.
He was left with a sore throat and had difficulty swallowing the next day.
Lancaster said: "I think four years off rugby should help learn the lesson, I don't think going to the police is necessary."
Rolleston club president Paul Frewen strongly condemned Ilalio's actions.
"Violence is not acceptable anytime, or anywhere," he said.
"This type of behaviour is deeply concerning and does not reflect our values as a club.
"We have visited the player involved and are offering support and guidance."
Sub union chairman Chris Thornley said Ellesmere was mortified by the incident. It was the longest ban he had heard of.
"Up until now we've had one of the best track records of on field and off field behavior," he said.
"For this to occur is quite stressing to be fair, there's no place in the game for people like this."