Big-spending Port ended their five-game winless streak in Thai League 1 with a 2-1 home victory over newcomers Lampang on Sunday night.
Hamilton Soares struck twice in a span of less than 10 minutes early in the first half for Port at PAT Stadium. Thiago Rodrigues pulled one back for Lampang two minutes from time.
The visitors also had Wutthichai Marom sent off in injury time after picking up a second yellow card warning of the match.
Port moved up to seventh place in the league with 14 points while Lampang were in 13th spot with seven points, just one above the red zone.
In other matches last night, former champions Muang Thong United were handed a 2-1 loss at Police Tero and hosts PT Prachuap edged bottom-placed Lamphun Warriors 1-0.
The battle for the possession of the top spot was decided on Saturday night.
Defending champions Buriram United took their tally to 23 points from nine matches following a 3-1 victory over visiting Nongbua Pitchaya.
What really mattered was that Chonburi fell to a 22nd-minute goal from Heberty Fernandes which sealed three points for Bangkok United.
Chonburi slipped to second place with 21 points, one more than Bangkok United who have a game in hand.