Sonny Bill Williams knows there is a chance he could be playing his last game of rugby in New Zealand this Friday night.

SBW will head to Japan to take up a lucrative new contract after the Super Rugby season wants to help the Chiefs make their second visit to the grand final in 17 years.

Williams is no stranger to big matches, having played for the Crusaders last season, experienced the All Blacks' World Cup winning campaign ,and been through some big playoff games on the way to winning the NRL title with the Canterbury Bulldogs in 2004.

Williams said the semifinal would be a step up from any other game the Chiefs had played all year.

The Chiefs will host the Crusaders at 7:35pm this Friday while the Sharks face the Stormers at 3:05am Sunday.

Story by: Akuila Cama