The Arsenal winger settled the contest in the 95th minute after Japan had threatened a famous upset, with Kaishu Sano's first-half opener cancelled out by Casemiro before Martinelli's late intervention sent the five-time world champions through.

Brazil will now face either Ivory Coast or Norway in the Round of 16 as Carlo Ancelotti's side continue their pursuit of a first World Cup title since 2002.

Japan stunned Brazil after 29 minutes when Sano capitalised on a misplaced pass from Danilo, surged through midfield and calmly slotted beyond Alisson to hand Hajime Moriyasu's side the lead.

Brazil gradually took control after the interval and were rewarded when Gabriel's inviting cross found Casemiro, who rose unmarked at the back post to head home and restore parity.

The momentum remained with Brazil for the remainder of the second half. Vinicius Junior struck the post as Japan were forced deeper and deeper, while Zion Suzuki produced several important saves to keep the scores level.

Extra time looked inevitable until Martinelli arrived in stoppage time to apply the decisive finish, breaking Japanese hearts and sending Brazil into the last 16.

Japan exit the tournament after another spirited display, while Brazil's World Cup campaign continues with a place in the quarter-finals at stake.

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