Blackpool were edged out by the North West Counties League first division north leaders in a Liverpool thriller, with six of the seven goals scored before half-time.
Lower Breck scored all their four in the first half, including a brace by Stephen Milne, to maintain their six-point lead at the top, while the Mechanics have slipped a spot to fifth.
The hosts took the lead in the third minute, when Jamie Morton headed in from a corner.
The Mechanics battled back and equalised in the 20th minute as Lewis Simmons’ header went over the keeper and in.
Milne’s first goal put Breck back in front 10 minutes later – a good move which saw the striker go past keeper Alex Cameron to score.
He added his second just six minutes later and the home side looked to be in control at 3-1.
However, AFC again hit back two minutes before the interval as Billy McKenna’s fine effort found the top corner.
But there was still time for Breck to restore their two-goal cushion before the interval, Thomas Kinsella scoring after some impressive build-up play.
The Mechanics refused to concede defeat and put the leaders under plenty of pressure in the second half.
However, the visitors had to wait until the 87th minute for their third goal, though it was one to savour as Conah Bishop fired home a terrific effort from 30 yards.
But it wasn’t enough for Blackpool and Lower Breck held on for their 15th win in 23 league games.
The Mechanics will be out to regain their top-four spot when they face St Helens Town at home on Tuesday (7.45pm).