STEPHEN O�NEILL broke Kelty Hearts by netting a dramatic injury time winner to secure a massive three points for Colts at Broadwood.
Colts took the lead against one of the title favourites courtesy of Marty Wright's opportunist first half strike, but the visitors from Fife hit back late in the game when Nathan Austin equalised.
However, the Cumbernauld men showed great character and in particular their talisman O'Neill whose decisive late finish secured an impressive win for Colts and moved them into the top three of the Lowland League.
Kelty created the first chance of the game in 11 minutes when Garry Cennerazzo did well on the right and picked out Cameron Russell inside the six-yard box where the winger should have scored, but he volleyed wide from close range.
Colts were holding their own in the midfield battles and worked hard to forge some goal scoring opportunities, and in 25 minutes a great counter attack saw Fraser Team race clear on the right and drill a cross towards the back post where Lewis Bonar was poised, but Cennerazzo did very well to cut out the danger.
A minute later after yet another good Colts counter attack Team attempted an audacious overhead kick from the edge of the penalty box, but it didn't trouble Kelty keeper Ben McKenzie.
It was the visitors turn to go close again on the half hour mark when they won yet another free kick on the edge Colts box, and dead ball specialist Scott Linton stepped up to send a curling effort beyond the reach of Colts keeper Jonathan Grier, but the strike scrapped the outside of the left-hand post.
This thrilling encounter was now wide open, and Colts had two great chances in quick succession when Bonar was inches short of getting onto O'Neill's low cross and then Wright hooked a volley just wide of McKenzie's left-hand post.
Kelty then came closest so far to opening the scoring in 36 minutes when former Clyde man Linton stepped up to another free kick from the edge of the box which he smashed off the face of the cross bar with Grier helpless.
The healthy crowd sensed the opening goal was coming for either side and it came the way of the hosts in 40 minutes when Craig Murray fed Wright on the edge of the box and the experienced striker turned superbly before drilling a powerful low shot low past McKenzie.
The Fifers almost hit back immediately and yet again it was that man Linton with another free kick this time from the right side of the box which cannoned off the top of the bar with Grier rooted to the spot.
There wasn't much to separate the teams at the start of the second half, however Kelty had a great chance to draw level on the hour mark when they were awarded a penalty after Chris Dodd was pulled down by Colts sub Michael McAnespie. But Colts keeper Grier produced an outstanding save from Linton's spot kick.
And then a minute later Grier was the Colts hero yet again making a tremendous double save from Austin and then Cameron Russell as Kelty continued to probe for an equaliser.
The next goal was going to be crucial and in 73 minutes Colts should have doubled their advantage when Bonar outmuscled Cennerazzo on the edge of the box and ran in on goal but his tame effort from close range was blocked by McKenzie.
And then again in 80 minutes Bonar had another great opportunity which he created himself driving towards goal from the right wing before sliding a shot towards the far post, but again McKenzie made a good stop to deny Colts.
However, the visitors were growing stronger as the game drew to a close, and in 87 minutes they grabbed a deserved equaliser when a long ball into the Colts box was misjudged by Scott Davidson and danger man Austin pounced on the error before calmly prodding the ball beyond Grier from close range.
But the game's defining moment arrived two minutes into injury time when Team broke free on the right and after some intelligent hold up play Team released O'Neill through the centre of the Kelty defence and the winger held off Daniel Ashe before thumping the ball low past McKenzie from 10 yards to send the Colts fans into ecstasy.
Colts will now aim to continue their impressive start to the season when they host league newcomers and current leaders Bonnyrigg Rose to Broadwood this Friday evening.
Kelty Hearts; McKenzie, Cennerazzo, Linton, Bragg, Ashe, Treilly, Husband, McKirdy, Austin, Russell, Dodd. Subs; Philp, Campbell, Trialist, O'Neil, Jardine.