Defending champions Buriram United recorded an eighth consecutive Thai Premier League win to maintain the pressure on the top two.
With Muang Thong United and the unbeaten BEC Tero Sasana having both won on Saturday to retain a share of the lead, Buriram were under pressure to deliver the following day.
And they did just that, running out 2-0 winners at Ratchaburi to remain within one point of top spot, Jakkraphan Kaewprom and Javier Patino Lachica with first-half goals for the visitors.
Wuttichai Tatong struck the only goal late in the game for Muang Thong as they beat 10-man TOT to stay at the summit on goals scored.
Tero Sasana are still level at the top following an eventful triumph on the road over Suphanburi, Jose Alves' men eventually winning 3-2.
Jaturong Pimkoon gave the away side the lead in only the 10th minute only for Robert Cullen to level within 60 seconds.
Not to be deterred, Tero Sasana came back after the break and secured victory thanks to goals from Sho Simoji and Naruphol Ar-Romsawa.
Suphanburi did pull a goal back through Birame Diouf, but their day ended in double disappointment as Adisorn Promrak was shown a red card in the final minute.
Four other teams in the top 10 also claimed maximum points on a dominant day for the top half of the table, with Ratchaburi joining Suphanburi and TOT in suffering defeat in round 21 of the season.
Goals from Kanu and Nurul Sriyarngem gave Chonburi a 2-0 win over Songkhla United.
A Renan Marques double gave Chiangrai United a 2-0 success over PTT Rayong, while Singhtarua were held to a goalless draw by Osotspa Saraburi.
Bangkok United made it back-to-back wins as they beat Sisaket 3-1, including a second goal of the season for Mali midfielder Kalifa Cisse.
At the bottom Samut Songkhram are 11 points from safety after falling to a fourth successive defeat as they were beaten 2-0 by Bangkok Glass
Meanwhile, fellow strugglers Air Force Central and Chainat Hornbill both recorded 1-1 draws against Police United and Army United respectively.