Chiefs number eight Sione Lauaki has lost a lucrative Japanese rugby contract because he was facing an assault charge.

Laukai was fined $800 and ordered to pay $500 for emotional harm to a man he assaulted in March because he thought the man stole his drink.

Appearing in Hamilton District Court today, Lauaki was also convicted of careless driving.

Outside court Lauaki expressed his regret.

"Looking back now, it's something silly that happened that night. I'm glad it's dealt with," Lauaki said of his assault.

Lauaki had previously pleaded guilty to the assault charge for the incident in Hamilton in early March, when he punched the man twice after thinking the man had taken his drink.

The New Zealand Rugby Union fined Lauaki $4000 over the assault and said it would terminate his contract should there be another incident.

Lauaki's other conviction, for careless driving, today earned him a $400 fine and $545 in reparations. He was also disqualified from obtaining or holding a drivers licence for two months.

The careless driving charge came after a crash in Waikato in April, the morning after a Super 14 match against the Cheetahs in Hamilton, when he rolled his car near Huntly. Blood tests showed Lauaki was well under the legal drink-driving limit.

Last year, Lauaki attended an anger management course after he was charged with damaging windows and a TV set at a motel. In 2006, he was offered police diversion after assaulting a doorman.

In court today Judge Connell acknowledged Lauaki had already suffered as a result of his actions, including losing a Japanese contract and having to pay $4000 to the Waikato Rugby Union.

Lauaki played the last of his 17 tests against Samoa in September 2008.

He has secured a contract with French rugby club, Clermont.

- with Newstalk ZB, NZ Herald staff