A late three-goal scoring spree by Bangkok United sent defending champions Chiang Rai United falling headlong down to ninth place in the Thai League 1 charts on Saturday night.
The 4-1 away rout exposed the Beetles' defensive inadequacies and put their new coach Masami Taki under even more pressure after just one win in four outings.
It was Bangkok United's fourth straight win in as many games and it gave them the sole possession of the top spot in the league at least for a few hours.
Bangkok United's convincing victory also mounted pressure on Klong Toey-based Port to go all-out for an away win against six-time champions Buriram United in their mouth-watering encounter tonight.
Hosts Bangkok United went on the attack from the beginning of the match but their unrelenting efforts fell short of getting them off the mark.
It was the Beetles instead who struck first when a ballooning header by Brinner Henrique off a corner found its way into the net shortly after the half-hour.
Bangkok United needed only a few minutes to get even as Manuel Tom Bihr latched on to a Vander Luis free-kick and tapped it home at the far post from close range.
The match seemed heading for a draw before the home team unleashed a 10-minute scoring blitz that helped them add three goals to their final tally.
Japanese midfielder Hajime Hosokai kick-started the Bangkok United scoring spree with a strike in the 84th minute.
It was followed by goals from Brenner Marlos and Sarawat Detchmitr in the dying moments.
Meanwhile, reigning League Cup champions PT Prachuap's nightmarish start to the season continued as they were beaten 3-2 by Sukhothai at their own Sam Aoh Stadium.
Sukhothai got their first goal in the 14th minute from Evandro Nascimento, but Prachuap were able to level the score through William Henrique nine minutes later.
John Baggio ensured that the visitors went into the breather with a 2-1 advantage with a goal in the 37th minute.
Sukhothai widened the margin after the break with Ibson Demelo being on target before William Henrique converted a penalty for Prachuap to make the scoreline look respectable.
Hosts Rayong FC remained without a point after four matches, going down 1-0 to Suphanburi.
The winning goal came during the injury time with Thinnakorn Asurin finding the net for the visiting team.