Sunwolves fullback Kotaro Matsushima has extra reason for the Japanese Super Rugby side to come away with a win against the Sharks this weekend.

The 24-year-old, who was born in Pretoria, South Africa, to a Zimbabwean father and Japanese mother, joined the Sharks Academy in 2012 after graduating from Yokohama's Toin Gakuen High School, having previously spent one year while at junior high school in South Africa.

Matsushima spent a year in Durban, representing the Sharks at under-19 and under-21 level and was even picked for a training camp for the South Africa under-20 side.

"My teacher from high school thought it would be good for me to go there and because I was born in South Africa, the Sharks wanted me," he told Kyodo News on Friday following the Sunwolves' captain's run at Singapore National Stadium.

"I just remember how big the contact was. The forwards were big so as a back it was easier as we were often going forward. It was a good experience."

Matsushima left Durban when he was called up by Eddie Jones to the Japan squad in 2013 and joined Suntory Sungoliath the following season.

"I had no regrets at all about leaving. My parents were in Japan and so were all my friends."

With such a new side, Matsushima cannot recall playing alongside any of the current Sharks side but he certainly knows what type of rugby they will play.

"They are going to use their forwards to bash our backs," he said. "So our mindset is to tackle low, double tackle. We have to be mentally strong every second."

And when the Sunwolves do get the ball, the flying fullback said he would be looking to link up with speed merchants Kenki Fukuoka and Shota Emi or look to gain territory with the boot.

"I will try to find the mismatches with the forwards. If not kick back to the space."

"It's a big chance for us. We just have to turn our mind to it, be more confident in our skills and play smarter."