Thiago Cunha netted twice as Chonburi won 2-1 on Thai Port's TPL swansong.
Both sides wasted early chances with Thiago knocking the ball into Wanlop's legs after being sent on his way by Jetsadakorn while Steven Robb missed a sitter with the goal gaping at his mercy.
Thai Port fell behind on 12 minutes when a long ball caught Termchai napping which allowed Thiago the easy task of stroking the ball past Wanlop.
Ten minutes later, another long ball from Chonburi was this time missed by Thongchai and as the left back tried to retrieve the situation, he fouled Thaigo in the box. It was a rather harsh award by the referee, but Thiago wasn't complaining as he coolly sent Wanlop the wrong way to make it 2-0.
However, the hosts began to find their feet with Sarawut fizzing an effort across the goal and Ri Myong Jun headed onto the post after a teasing cross from Robb.
Steven Robb then atoned for his earlier miss when he prodded home Watson's low cross on 45 minutes to give Port a glimmer of hope.
The clock whittled down slowly after the break with few chances for either side. Robb blasted a shot into Sinteeweechai's midriff while Ri Myong Jun's spin and shot in the box flew wide. The closest the Sharks came was when newly introduced sub, Paritas, fired over the bar from close in.
At the end of the game, there was a pitch invasion from the Klong Toei youngsters as they went in search of goodies from the players. Both sides now have about three months to prepare for next season. The pair might be in different divisions but the target of winning their respective leagues will be the same.