Chiang Rai United beat BG Pathum United 2-0 to hand the champions their first loss of the Thai League 1 season on Wednesday night.
The Beetles raced to a 2-0 lead in the first half with goals from Felipe Amorim in the 28th minute and Phitiwat Sukjitthammakul just before the interval.
The Rabbits were clueless without three key players -- defenders Victor Cardozo and Andres Tunez and striker Diogo Luis Santo who are all recovering from injuries.
Hosts Bangkok United defeated Prachuap 2-1. Pokklaw Anan opened the scoring for the capital side in the 10th minute.
Saharat Pongsuwan equalised for the visitors in the 66th minute and Chananan Pombuppha scored the winner in the 88th minute.
On Tuesday night, Muang Thong United drew 1-1 draw with Nongbua. Hamilton Soares' spot-kick gave Nongbua the lead after four minutes and Sardor Mirzaev equalised for the hosts with a penalty-kick 10 minutes later.
