Cape Town - Chiefs centre Sonny Bill Williams says it was a tough decision to turn his back on the All Blacks for lucrative deals in Japan and Rugby League.

Williams last week announced that he had signed with Japanese side Panasonic, in a deal reportedly worth $1.4 million, and would then switch to an unspecified National Rugby League (NRL) team in Australia.

“It was a pretty tough decision but I had an agreement to go back to the NRL next year, he told Eyewitness News Sport.

“I could have stayed around to play in the Rugby Championship but then Japan came with an offer. First I turned them down before they came with another that I would have been crazy to turn down.

“I’ve chosen to embrace it and go over there and enjoy myself. It will be pretty cool to see what’s happening over there."

The Chiefs finished second on this year’s Super Rugby log and Williams is eager to help them win the Super Rugby competition for the first time in their history.

“I want to leave New Zealand on a high. A lot of people wrote us off at the start of the year but we knew as a team that we had a lot to prove. That’s what motivated us, we were all in the same boat; we’re a new franchise, not just players but as coaches too, and we had something to prove and we’ve done that so far.

"But we’ve lost our last two games on the trot and it’s been pretty tough. This week hopefully we can fix a few things and get to where we were before that break.”

Williams was also set to play in the lucrative George Sevens event later this year. But with his move to Japan, it appears to be off the cards.