Cambodia host Japan on Tuesday, hoping to avoid a seventh successive defeat in World Cup qualifying.
Japan moved to the top of Group E after securing a comfortable 3-0 win over Singapore on Thursday and now hold a one-point lead over nearest challengers Syria after five matches.
Mu Kanazaki and Keisuke Honda scored first-half goals for Japan before Maya Yoshida wrapped up all three points with a late strike.
Vahid Halilhodzic's side - who were the first side to qualify for the 2014 World Cup - travel to Phnom Penh in search of more goals.
"I'm very happy for the victory, we played with ambition and aggressiveness [but] unfortunately we couldn't score more goals," the head coach said.
"We had to score three more goals ... we have to continue to try and search for progress, individually and collectively."
Bottom-of-the-table Cambodia were beaten 3-0 by Afghanistan on Thursday, slumping to their sixth consecutive loss in the group.
Lee Tae-hoon's side have scored just one goal, conceding 19 times.
Japan beat Cambodia 3-0 at home in September with a weakened side and are expected to see off their opponents with relative ease at the Olympic Stadium with the attacking talent of Honda, Shinji Okazaki and Shinji Kagawa all available.