
Defending champions suffered a shock home defeat, going down to Port 1-0 in a Thai League 1 clash on Sunday night.
Khlong Toey-based Port did well to hold on to the advantage Chinnawat Wongchai gave them in the 25th minute until the very end to secure three points from the game.
Despite the defeat, the Thunder Castle remained eight points ahead of second-placed Bangkok United, who have a game in hand.
Buriram coach Osmar Loss Veira apologised to the fans and blamed the loss on "numerous mistakes" his men committed during the match.
In other games on Sunday night, Bangkok United picked up three valuable points with a 2-1 home victory over Nakhon Ratchasima.
Sukhothai lost 3-1 at home to former champions Muang Thong United, PT Prachuap hammered hosts Khon Kaen United 4-1 and Chiang Rai United continued their revival with 3-0 rout of Nakhon Pathom United.
Hudson new Rabbits coach
Meanwhile, BG Pathum United have officially announced Anthony Hudson as their new coach.
Hudson has coached New Zealand, Bahrain and United States of America national teams in the past.
He joins the Rabbits from Qatari club Al Arabi.