Ulsan had looked to be second best for much of the match, and an early mistake by their defence had almost gifted Romulo the opener, but the Brazilian striker snatched at his shot, dragging it wide of the target from just inside the penalty area.

By the eighth minute, Ulsan should have been in front. Darijan Bojanic powered towards a backpedalling Chengdu defence, feeding Lee Hui-gyun on the right and his cross towards the far post was volleyed spectacularly but wastefully across the face of goal by Markao.

Ulsan survived another scare in the 33rd minute when Felipe stole possession and drove down the left side before sending in a low centre that the late-arriving Tim Chow side-footed agonisingly wide of Jo Hyeon-woo’s left post.

Baek In-woo forced Jian Tao into a routine save after cutting inside from the left flank to shoot towards goal from 30 yards before, moments later, the visitors took the lead.

A miss-hit clearance by Lee Hui-gyun after Romulo’s shot was blocked fell in the path of De Erjiaduo and he slotted his first-time right-foot shot into the bottom corner of Jo’s goal.

Bojanic squandered the opportunity to pull Ulsan level in the 62nd minute when he bobbled an effort wide from inside the area as the hosts countered while Jian pushed Erick Farias’ attempt from outside the area to safety seven minutes later.

Jian pulled off a fine save in the 71st minute tipping Lee Hui-gyun’s dipping strike from 20 yards out onto the top of the crossbar as Ulsan started to increase the pressure on the Chengdu defence.

The equaliser finally came with 14 minutes remaining, Bojanic slipping his pass through to Um Wong-sang from deep. The substitute hit goalkeeper Jian with his initial effort before steering the rebound in via a deflection of defender Li Yang.

Jian then denied Erick Farias in the dying moments and Um Wong-sang had fired across goal seconds earlier before Heo delivered the late killer blow .