David Rochela's 86th-minute strike looked to have given the champions all three points, only for Brazilian striker Aron to level two minutes from time to ensure a share of the spoils for the visitors.
Second-placed Chonburi took full advantage of the league leaders' slip-up, cutting the gap at the top to two points with a 2-1 win over Sisaket thanks to goals from Krirkit Thaweekarn and Boworn Tapla.
However, BEC Tero Sasana's chances were dealt a huge blow by Ratchaburi, who sealed a 2-1 away win to leave the hosts eight points behind Buriram with efforts from Brazilian duo Douglas and Heberty, who further cemented his position as the league's top scorer with his 22nd goal of the season.
Muzafer Ejupi scored a second-half winner as Songkhla United kept their hopes of survival intact with a 3-2 away success at Bangkok Glass, but Air Force Central could be relegated on Wednesday following a 1-1 draw with Army United.
