Buriram United tied Chiang Rai United at the top of the Thai League 1 table despite a toothless show that produced a close 1-0 home win over relegation-threatened Chainat on Sunday night.
After missing a host of opportunities, the defending champions were able to break the deadlock midway through the second half when Supachok Sarachat delivered the winner for the Thunder Castle.
Buriram's tally now stands at 51 points, the same as the Beetles.
Also last night, hosts Chiangmai were left on the brink of a return to the second tier as they lost 2-0 to Port, who are in third place with 46 points.
Both Port goals came in the second half with Josimar Rodrigues and Kevin Deeromram scoring in quick succession after 70 minutes.
In Saturday night's late game, Chiang Rai United let an under-strength Bangkok United side escape with a 1-1 away draw that left the Beetles' coach Ailton dos Silva calculating his team's chances of winning the league for the first time.
"It's a pity that we could not win this game, but I would say we were quite lucky to have picked up a point tonight," said Silva. "It's a very tight race so one point could make a lot of difference in the end.
"We have three matches left, we have to win all of them.
"We came here to win but Bangkok United played very well considering that they were involved in a 120-minute game in the FA Cup in the midweek."
Chiang Rai's Bill Rosimar found himself in a one-to-one situation with Bangkok United goalkeeper Michael Falkesgaard and the Brazilian forward made the most of the opportunity to put the Beetles ahead in the 16th minute.
Peerapong Phichitchotirat fouled Bangkok United playmaker Sanrawat Detchmitr inside the box and Vander Luis converted the 64th-minute penalty to put the home team back on level terms.