BEC Tero Sasana and Chonburi are the only sides with unbeaten records in the Thai Premier League after Ratchaburi and Singhtarua both lost.
Chonburi continued their bright start to the campaign, climbing to third as goals from Anderson Dos Santos and Thiago Cunha gave them a 2-1 victory over Samut Songkhram.
Yusuke Kato netted a consolation for Samut, but Somchai Chuayboonchum's men remain bottom of the table and without a win this season.
BEC Tero Sasana moved to fourth after posting a 2-1 triumph against Sisaket. Georgie Welcome and Sho Shimoji scored, meaning Pak Nam-Chol's late consolation meant little.
After five wins in their opening seven matches, newly promoted Singhtarua lost their league lead after falling to a surprise 2-0 defeat at TOT on Wednesday, while Ratchaburi were beaten 2-1 by Osotspa.
A penalty from Takahiro Kawamura and Prakit Deeporm's second goal of the season secured victory for TOT.
Ratchaburi looked to have rescued a point against Osotspa when Douglas levelled proceedings with 12 minutes left - only for Tangeni Shipauhu to score an 87th-minute winner.
Muang Thong United are the new leaders after their comprehensive 4-1 victory over PTT Rayong. Mario Gjurovski netted a first-half double for the winners, while Teerasil Dangda also got on the scoresheet.
Air Force United continue to search for their first win of the season after they were beaten 2-0 by Chiangrai United, while Bangkok United dropped to 18th after a 1-0 defeat to Songkhla United.
Elsewhere, Army United ended a two-game losing streak with a 3-2 win over Bangkok Glass, Chainat collected a 2-1 win over Police United and Buriram United held Suphanburi to a 1-1 draw.