In a dramatic turn of events on the last day of Thai League 1, Sukhothai and Chainat both survived in the top flight but Bangkok Glass were sent tumbling down to the second division for the first time in the club's history.
Chainat finally managed to pull themselves out of the drop zone with a 2-1 victory in a cliffhanger at Suphanburi on Sunday night. Bernard Henri was Chainat's hero, netting both of their goals with the second being an injury-time penalty.
Sukhothai earned another year in the top division following a hard-fought 3-2 home win over bottom-placed Air Force Central.
Bangkok Glass, who only needed a draw in their last game to stay put in the league for an 11th straight year, conceded two goals to go 2-1 down to visiting Nakhon Ratchasima on Sunday night.
Chainat and Bangkok Glass were left with identical 42 points, but the Hornbills were ranked a place above the Glass Rabbits in final league standings because of a better head-to-head record.
Chainat whipped the Glass Rabbits 5-2 in the first half of the league and the second game between the two sides had ended in a 1-1 draw.
Bangkok Glass seemed well placed to survive as they were given the lead at the half-hour mark by Daniel Garcia, but then the Rabbits were dealt a triple blow from which they never recovered.
After Akekanat Kongket had levelled the score for Nakhon Ratchasima in the 35th minute, Bangkok Glass conceded a penalty when Tanaboon Kesarat was sent off five minutes before the break. Leandro Assumpcao landed the free-kick he had earned into the net to make it 2-1 for the visitors.
SCG Muang Thong United, who sacked their coach Radovan Curcic on Friday, were held to a goalless draw at home by True Bangkok United, while champions Buriram United wrapped up their league matches with 1-0 win at Ratchaburi.
In other matches last night, Chonburi tied Chiang Rai United 1-1, Port beat Pattaya United 4-1, Ubon UMT United defeated Navy 3-0 and Police Tero edged PT Prachuap 2-1.