The Japan women's development sevens side made instant friends with the crowd at Lawaqa Park on Thursday as they opened their account at the Fiji Coral Coast Sevens with two big wins.

And they also impressed a man who knows more than most about sevens at the highest level.

South African Rasta Rasivhenge was the man in charge of the men's gold medal match at the Rio Olympics and has refereed on the Sevens World Series since 2011-12.

(Rasta Rasivhenge (C) at the Fiji Coral Coast Sevens at Lawaqa Park in Sigatoka, Fiji, on Thursday.)

"They played really well. They're very skilled and their offloading game is really entertaining," said 32-year-old Rasivhenge, who also officiated in the Sunwolves' Super Rugby win over the Blues in July 2017.

"They may be small in stature but they don't commit too many to the breakdown and scored some brilliant tries."

Rasivhenge, who is something of a cult hero in Fiji, was particularly impressed by high school girls Hana Nagata and Rinka Matsuda, and Ai Hirayama, who at 25 is the oldest member of the squad.

"The way they used dummies to manipulate the defense and create gaps was outstanding."

"The more exposure they get to playing tough teams like this in these types of competition, the more skilful they will become and the wiser they will get to using their strengths to their advantage."

(Hana Nagata of the Japan women's sevens development squad tackles during a pool game against Hotspring Savusavu.)

Heading into Friday's second day, Makoto Inada's side showed they have every chance of improving on last year's runners-up effort and more importantly a number of girls showed they are capable of making the step up to the senior side as Japan build toward the Tokyo Olympics.

The Junior Sakura Sevens got their day underway with a 50-0 drubbing of Hotspring Savusavu with Matsuda bagging a brace of tries and captain Sora Nishimura, one of the four high school girls in the squad, weighing in with a try and four conversions.

Equally impressive was the defensive effort with Hotspring Savusavu never looking likely to score.

While they did give up one try to the Nadi Blazers in their second game, another brace from Matsuda ensured they ran out 31-7 winners.

Despite the wins, Inada said the team need to raise their level on the second day.

"We made too many easy mistakes in attack and defense," he said, before adding the recovery defense after the first missed tackle had been good. "We need to be more patient."

However, like Rasivhenge, he did have praise for Matsuda.

"She showed really good positioning and speed. She is a really good player," he said of the freshman at Kokugakuin University Tochigi High School.

Inada's only concern, other than the number of errors, is the condition of Nishimura, who seemed very groggy when she left the field after taking a big hit against Nadi Blazers.

"We'll have to see. We don't know her condition right now," Inada said.

(Nagata looks to pass against Hotspring Savusavu.)