Matsushima’s emergence as a star on the Brave Blossoms, as Japan’s team is known, seemed fitting on a team that reflects the gradually growing diversity of Japanese sports. He and Japan’s popular captain, Michael Leitch, a New Zealand-born flanker of half-Fijian parentage, have joined the likes of the tennis star Naomi Osaka, the sprinter Asuka Cambridge and the N.B.A. player Rui Hachimura of the Washington Wizards as mixed-race Japanese athletes who have gained global celebrity.

But the rugby stars’ growing integration into Japanese culture and growing popularity were of little use in the shaky opening minutes of Friday’s match.

“One hundred percent we were nervous, but once we got the nerves out of the way, we have started the way we wanted to,” Leitch said. “We showed great resilience, and we didn’t go into our shell. We kept playing and did a lot of work to play with purpose and be in the right spots.”

Japan’s nerves were evident almost immediately. In the fifth minute, Japan fullback William Tupou muffed a kick with no opponent near him, and the Russian winger Kirill Golosnitsky scooped up the ball and ran it in for a 5-point try, rugby’s equivalent of a touchdown. Flyhalf Yuri Kushnarev made the easy conversion to give Russia a 7-0 lead, and the partisan crowd of 45,745 sat in stunned silence.

The speedier Japanese team quickly picked up the pace, however, and after two clever offloads — the first a nifty no-look pass by outside center Timothy Lafaele — Matsushima scored the first of his three tries to close the gap to 7-5. Japan missed the conversion, though, and trailed for most of the first half despite having most of the possession, thanks to more errors and subpar kicking from flyhalf Yu Tamura.