The Chinese side trail Adelaide United, who also won on Wednesday, by two points and face them in a crunch final game in a fortnight. Changchun will need to win that home tie to progress to the quarter-finals.

They were quick to assert their authority against Binh Duong with Wang Bo's second-minute opener and goals from Guillaume Dah Zadi and Chen Lei before half-time.

Yan Feng's free-kick and a penalty from Samuel Caballero in the second half completed the rout.

Despite the heavy scoreline, it was the hosts who had the first chance of the game, Nguyen Vu Phong producing a good save from goalkeeper Zong Lei after 30 seconds.

But it was not a sign of things to come as the Chinese dominated thereafter, with an unmarked Wang heading home a corner with less than two minutes on the clock.

Eleven minutes later, Zhang Xaofei played a superb through ball to Dah Zafi, who coolly flicked past Nguyen The Anh.

Changchun made it three before the break as Chen raced clear to volley home. Anh managed to get a hand to his shot but it was too powerful for the stopper to keep out.

The one-way traffic continued after the break and Wang Dong missed a golden opportunity to stretch Changchun's lead when he blazed over an open goal.

The visitors finally added a fourth 12 minutes from time when Yan struck a free-kick into the top corner from 25 yards, and Caballero tucked home a spot-kick in the last minute after Zhang Xiaofei had been hacked down in the box by Anh.