Port defeated their arch-rivals SCG Muang Thong United 2-0 in the Thai League 1 at their PAT stadium on Wednesday night.
The result helped Port close the gap on leaders BG Pathum United to four points after 13 games. Muang Thong remained in ninth place on 17 points.
The match was rescheduled from Oct 4 after a power transformer blew up 30 minutes before the scheduled 6pm start of the game at PAT Stadium.
Port FC won their appeal against the Football Association of Thailand's (FAT) decision which handed the Thai League 1 club a 2-0 forfeit.
Former Thailand striker Adisak Kraisorn, who started up front instead of Nelson Bonilla, put the home team ahead in the 31st minute before the Salvadoran striker, who came on as a second-half substitute, made it 2-0 in the 86th minute.
Derley nearly put the Kirins ahead in the 17th minute but his shot went just wide at the near post while Kevin Deeromram also came close to breaking the deadlock for the home team.
Port finally got the goal they were looking for at the half-hour mark.
Kirins goalkeeper Dang van Lam parried a shot from Bordin Phala but the ball fell into the path of the unmarked Adisak, who fired home from a few yards out.
With the game heading into the final minutes, Bonilla, who scored in his first start for Port in their 2-0 victory against Chonburi on Saturday, made it two goals in as many games with a clinical strike from the right side of the box.
BEETLES PLAY FOR HONOUR
Thai League 1 champions Chiang Rai United hope to at least earn a point against Chinese Super League runners-up Beijing FC in their final Group E match of the Asian Champions League in Doha, Qatar, on Thursday.
The match will kick off at 8pm, Thai time, and will be shown live on Fox Sports and Bugaboo TV.
Beijing defeated the Beetles 1-0 when the two sides met in Chiang Rai in February before the conronavirus pandemic halted worldwide sporting activities.
Beijing, who have already qualified for the 16-team knockout stage, have amassed 15 points from five games. Second-placed FC Seoul, on six points, need only a draw against third-placed Melbourne Victory, who have four, to progress. Chiang Rai have four points.
A 2-2 draw with Melbourne Victory in the penultimate group game on Monday meant the Beetles have no chance of progressing in their ACL debut.
Chiang Rai will have three players back from suspension including Lee Yong-Rae, Sarawut Inpaen and Brinner Henrique.