Sebastian Quintana struck a second late equaliser in as many matches as Qatar earned a point against Asian Cup co-hosts Vietnam in Group B on Thursday.

Phan Thanh Binh's first-half goal following a horrendous goalkeeping error from Qatar'sMohamed Saqr looked to have fired Vietnam into the last eight in Hanoi.

But Quintana, who scored with two minutes remaining to salvage a 1-1 draw against Japan, headed home from close range with 10 minutes to play.

Qatar coach Dzemaludin Musovic, who was allowed to take his place on the bench despite being sent to the stands during the draw with Japan, was without suspended striker Hussain Yaser, while Messad Al Hamad was also omitted.

Musovic brought in attack-minded duo Magid Mohamed and Adel Lamy, while Vietnam coach Alfred Riedl kept faith with the side that stunned the United Arab Emirates with a 2-0 victory in the Group B opener.

Waleed Jassim and Quintana had early efforts easily saved by Vietnam goalkeeper Duong Hong Son, with neither side able to dominate the opening exchanges.

With any glimmer of an attack roared on by the capacity 40,000 crowd inside the My Dinh National Stadium, Vietnam's first real threat on goal came as Le Tan Tai's over-hit cross from the right narrowly dropped over Saqr's crossbar after 28 minutes.

A minute later Hong Son rescued his side with a full-length diving save after Quintana had broken into the area and fizzed a low ball across the face of goal.

Moments later Thanh Binh delighted the home crowd as Saqr allowed the Dong Thap striker's seemingly innocent low shot from just outside the area to squirm under his body and agonisingly roll over the line despite a desperate dive from the custodian.

Hong Son had to be on his toes to beat away Meshal Mubarak's dipping long-range drive before Jassim lifted Wesam Rizik's clever chipped pass into the area just over the crossbar in first-half stoppage time to bring to end a pulsating opening 45 minutes.

Quintana attempted a trademark free-kick just after the break, but the weak effort was smothered by Hong Son.

Mohamed came within a coat of paint of levelling the scores just after the hour mark as his flicked close-range shot struck the Vietnam post before Uruguay-born Quintana pulled the follow-up shot wide.

Le Cong Vinh almost made Mostafa Abdullah pay for a defensive slip with 15 minutes remaining, but the Song Lam Nghe An frontman pushed his shot high and side from a narrow angle.

The partisan crowd were silenced with 10 minutes remaining as Quintana headed home from close range after a deflected shot from substitute Ali Afef looped over Hong Son for the Qatar SC forward to bundle the ball in from under the crossbar.

Afef almost grabbed a winner with five minutes remaining as the Al Sadd striker beat the Vietnam offside trap and chipped the ball over an advancing Hong Son, but he could only watch as the ball struck the bar and bounced down the wrong side of the line.