Al Ghassani had threatened as early as the 12th minute, steering his header across the face of the Lion City goal when he met Jakkapan Praisuwan’s cross from the right while the Omani’s effort from distance soon after took a deflection on the way through to Ivan Susak.

Bart Ramselaar snatched at an effort in the Bangkok United penalty area in the 24th minute, the Dutchman hitting the ball harmlessly at visiting goalkeeper Patiwat Khammai after shooting on the turn 15 yards from goal.

Moments later Diogo Costa fired just wide as Lion City started to exert increased pressure while Rui Peres’ effort from 30 yards out was deflected over the bar.

It was with Lion City pushing into the Bangkok United half that the visitors took the lead. Weerathep Pomphan’s quick release from deep found Al Ghassani in an onside position and he coolly stroked the ball around Susek.

Anderson Lopes headed wide four minutes into the second half while Thy’s attempt moments later was blocked as the home side made a positive resumption after the interval.

Thy again threatened in the 65th minute but his shot was deflected wide by Patiwan’s outstretched boot and Lopes then headed wide after being found by Ramselaar’s cross from the left.

Thitipan Puangchan offered some respite for Bangkok United, firing off a shot that was deflected wide for a corner by the Lion City defence will a little over 10 minutes remaining and, three minutes later, the Thai side sealed the win.

Weerathep unlocked the defence again with a clinical pass from inside his own half into the path of Adzic and he made no mistake with a first-time finish across Susek and into the bottom corner.

Thy netted from close range a minute into stoppage time to give Lion City hope but the Singapore Premier League side were unable to find a second as Bangkok United held on.