Kwon Kyung-won's injury-time winner put Al Ahli into the final of the AFC Champions League for the first time courtesy of a 3-2 win at the Al-Rashid Stadium on Tuesday.
The hosts came into their semi-final second leg with an away goal following a 1-1 draw in Riyadh but last year's finalists Hilal scored twice more to put them on the verge of the final before Kwon fired home in stoppage time.
Ahli coach Cosmin Olaroiu promised not to sit back on their away goal and saw his side lead after 17 minutes when Rodrigo Lima tapped in captain Ahmed Khalil's pass from the left.
A sublime Everton Ribeiro chip before the break bolstered his side's hopes only for Giorgios Donis' men to mount an impressive comeback.
Ailton levelled six minutes into the second half before a stunning Carlos Eduardo strike from range completed the turnaround and looked to be sending the visitors through.
As Ahli got desperate, Ismaeel Al Hammadi was booked for diving when seeking a penalty, before Kwon benefited from a half-cleared cross.
The delivery from the right was palmed away by Abdullah Al Sudairy with Kwon quickest to react, sending his side into the final where Guangzhou Evergrande or Gamba Osaka will be their opponents.
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