Samoa began their World Cup campaign with a bonus-point 34-9 victory over Russia.
After a faltering first half, Steve Jackson's side emerged from the break with a renewed energy to score six tries overall and deny Russia a foothold at the Kumagaya Rugby Stadium.
"It was a tough game," Samoan captain Chris Vui said at full-time.
"We knew that Russia were going to come in that first 40 (minutes), that first 20 (minutes).
"We just had to stick it out and I'm pretty proud of how the boys came back in the second half."
Samoa's Alapati Leiua scored the only try of a first half that saw the Pacific Islanders become a depleted force for nearly 10 minutes.
Both Rey Lee-Lo and Motu Matu'u were sent to the sin bin for high tackles on Vasily Artemyev, with referee Romain Poite deciding a yellow card was sufficient despite apparent contact with the Russian's head.
The Bears added their first points to the board with two penalties from Yury Kushnarev, but still entered the break with just a narrow one-point lead over their opposition.
Samoa eventually hit their stride as the second half began, scoring three tries in just eight minutes.
Afaeseiti Amosa was responsible for the first, before Ed Fidow produced two tries in quick succession and Samoa began to ease into comfortable lead.
An effort from Lee-Lo and a second try for Leiua sealed the victory as Russia could only respond with a Kushnarev drop goal and were left trailing by 25 points.
"We're here to create a legacy," said Vui.
"You can see there that we didn't let any tries in, I'm proud of the boys."
Samoa now hold on to a narrow lead in Pool A, bettering Ireland and host nation Japan on points difference only.
Scotland sit second from bottom having played one and lost one, while Russia are last with two games and two losses to their name.
Russia v Samoa - Match Stats
Russia: (6) 9
Penalty: Kushnarev (19', 26')
Drop-goal: Kushnarev (48')
Samoa: (5) 34
Try: Leiua (16', 80'), Amosa (45'), Fidow (49', 53'), Lee-Lo (63')
Conversion: Pisi (50', 54')
Man of the match: Alapati Leiua (Samoa)