Melbourne City have suffered the first defeat of their Asian Champions League campaign and missed the chance to put one foot in the round of 16, falling to a 1-0 home defeat against Thai side Buriram United.
Winners by 2-0 in the reverse fixture two weeks prior, City had a new face in the dugout at AAMI Park for Buriram's visit: Aurelio Vidmar in his second game in charge after Rado Vidosic was sacked last week following a horror start to the A-League Men season.
But while he'd tasted victory in his first game in charge against Sydney FC, he watched on as his side failed to find a way through the 'Thunder Castle' defence at AAMI Park before being made to pay when Goran Causic fired home an 86th-minute penalty after a handball by Aziz Behich.
It came 10 minutes after a penalty shout from the Serbian was waved away despite VAR recommending Saudi referee Majed Al-Shamrani review his initial non-call of a potential push by Marin Jakolis.
Though still atop group H at the full-time whistle, the result heaps pressure on City heading into their final two ACL fixtures against Japanese side Ventforet Kofu and Chinese outfit Zhejiang.
Only group winners are guaranteed progression in the ACL, with the three best second-placed finishers from the East region to join them in the knockout stages.
City twice had goals disallowed for offside in the opening stanza, the first coming in the 29th minute when skipper Jamie Maclaren had a close-range finish ruled out and the second in the 41st followed up a saved effort from Maclaren.
But despite seeing less of the ball, Buriram, led by former Newcastle coach Arthur Papas, adjusted at the half and seized a win that keeps their own hopes of ACL progression alive.