As to be expected, the Asian outfit started off strong, dominating possession and would have opened the scoring early on but for a great save by Daniela Solera, as she denied Saki Kumagai's header from a corner. Despite facing 46 shots in their loss against Spain, Solera was looking impressive in the Costa Rican goal.
Then the dynamic of the game was completely changed in a two-minute spell as Japan scored twice in quick succession. First, Hikaru Naomoto capitalised on a slip by María Coto to reach a through ball from Mina Tanaka and she used her time and space to pick her spot before firing into the bottom corner.
Aoba Fujino then doubled her nation’s lead, driving home past Solera, to mark Japan’s seventh goal at the tournament so far from a sixth different goalscorer.
With a two-goal lead, the Japanese looked incredibly comfortable in the second half as they increased Solera’s save count for the tournament. Despite being second best for large parts of the second period, the Costa Ricans were doing well to keep the scoreline at 2-0.
However, a mixup at the back almost cost them a third goal as Solera and Fabiola Villalobos both went for a ball in the box under pressure from Riko Ueki, but somehow the defender managed to clear the ball behind the goal.
Villalobos then had her nation’s first shot on target at the tournament in the 81st minute, but Ayaka Yamashita was equal to it.
The Japanese, who have looked one of the most impressive teams so far in this tournament, eased to victory in the end, not having to exert themselves much in the second 45 minutes, and will have their place in the last 16 confirmed if Spain avoid defeat against Zambia.
They face the Spaniards next, in what could be a battle for top spot in the group.