Venlo midfielder Keisuke Honda's shot in the 20th minute was saved by goalkeeper Miguel Pinto, but Okazaki quickly hit the rebound into the net. Only four minutes later, the lively forward received a pinpoint cross from captain Yuji Nakazawa, and fired home his second goal of the day after beating two defenders.
"The first one was a rebound and the second one was a nice cross. I'm really happy that I was able to score," said Okazaki. "We are determined to beat Uzbekistan in the World Cup qualifier to keep the momentum."
Japan controlled the game well in the first half with Yasuhito Endo, Keiji Tamada, Okazaki and Honda hitting shots on goal. Chile's biggest chance came in the 39th minute, when striker Fabian Orellana was set free in the area with goalkeeper Seigo Narazaki out of position, but his shot went over the bar.
Forwards Edson Puch and Jose Fuenzalida came on for Chile after the break, but it was Japan who scored first in the second half when midfielder Yuki Abe headed home a corner by Endo in the 52nd minute.
Japan missed a chance in the 63rd minute, when Kengo Nakamura was set free by a long ball but failed to find the target. However, after Fuenzalida missed an opportunity to reduce the deficit, substitute Kisho Yano and Naoki Yamada combined to set up Honda, who made it 4-0 in injury time.