By Gabriel Tan
The Stags found themselves 2-0 down after 47 minutes on Sunday at the Clementi Stadium after the Bulls netted through Julien Durand and Jung Hee-bong.
However, Tampines never gave up and pulled one back in the 65th minute through captain Aleksandar Duric, before Mustafic Fahrudin equalised from the spot six minutes from time.
And while the defending champions might have been forgiven for settling for a point, substitute Jamil Ali secured all three when he scored a stunning solo effort three minutes into injury time.
Speaking after the game, Tan admitted he would have been satisfied with a draw, and that his players were slightly lucky to come away with all three points.
"I would say we were lucky to come away with all three points," the former Singapore international conceded. "I would have been satisfied with a draw.
"In the first half, we always seemed to be second to the ball, but I'll give the players the benefit of the doubt as I think some of them were tired.
"Credit to them - they never gave up, and the equaliser gave them confidence [they could grab the win]."
Tan also singled out Jamil for praise, after the 28-year-old struck in stoppage time for the third time this season.
"Jamil has been struggling with a hamstring injury, but I told him he'll come on for the last 20 minutes," Tan added.
"In the end, he did really well."
Gombak coach K. Balagumaran cut a forlorn figure after the game, admitting his side had thrown away the game.
"I would say that was our most disappointing game of the season," Balagumaran revealed. "The game was there for the taking.
"We played well, but in the second half we sat back too deep."
The Bulls tactician also believed Tampines should not have been awarded a spotkick in the 86th minute, after Obadin Aikhena was adjudged to have tugged back Duric in the box.
"That was definitely not a penalty," Balagumaran added.
Gombak will aim to bounce back on Sunday when they entertain Geylang United, while Tampines will be looking to make it four league wins in a row when they visit Albirex Niigata.