Masashi Motoyama put the home side in front in the first half and then added a second shortly after half-time. Marquinhos bagged a brace before Yuzo Tashiro and substitute Danilo completed the scoring.

Kashima have now scored 15 goals in their first two games in Group F, after a 9-1 demolition of Krung Thai Bank in Bangkok last week.

Nam Dinh keeper Bui Quang Huy kept the home side at bay in the opening exchanges but he could do nothing about Motoyama's superb volley in the 26th minute.

Four minutes after the restart, Motoyama ran on to Mitsuo Ogasawara's pass and wrong-footed defender Tran Van Toan before driving a low shot past Huy at his near post.

Motoyama then turned provider for Kashima's third in the 58th minute. His through ball played in Atsuto Uchida, who clipped the ball over Huy to an unmarked Marquinhos, who headed into an empty goal.

Marquinhos grabbed a second when he glanced home Uchida's cross from the right and Kashima made it five in the 74th minute when Tashiro rose to head home a corner.

Another cross from Uchida allowed Danilo to curl a superb shot into the top corner late on.