Belper made the trip knowing the tie would have to be played to a finish.
At kick-off the weather was most unpleasant with icy rain and strong winds blowing down the pitch.
Belper had the kick-off and had the advantage of the wind for the first 45, with the wind was making it hard for Buxton to clear their lines and Belper had most of the possession going forward.
This resulted in some long-range efforts but nothing to seriously trouble the Buxton keeper.
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Belper then had a number of corners in quick succession and it was direct from the corner that Emma Brentnall gave Belper the lead as her corner flew straight in at the far-post.
Belper came close to scoring a second from another Brentnall corner when Leah Parkins’ shot was cleared off the line.
As half-time approached Buxton started to cope with the wind and brought themselves back into the game, as they had a number of counter attacks with some fast passing through the middle, but it was Belper who went in at half-time a goal up.
The second half was always going to be back to the walls as Buxton now had the wind with them and were desperate for an equaliser early on and Emma Varnam had to push a long-range effort on to the bar within five minutes of the re-start.
As Buxton continually peppered the Belper goal, the visitors eventually buckled ten minutes before the end to ensure extra time.
The first 15 minutes of extra-time was much the same as the second half as Buxton went with the wind, but again Varnam was not to be beaten as she made a double save low to the right.
As ends were swapped at half-time Belper were full of energy playing with the wind behind them and Tunnicliffe, Parkin and Harper pressured the Buxton back line as the half wore on.
However, neither team could prevent spot-kicks.
Belper were first up with Wheatley who calmly slotted home, before Buxton hit the crossbar.
Tunnicliffe’s penalty was then saved, before Varnam kept out Buxton’s second to maintain Belper’s advantage.
Brentnall scored the third penalty and again Varnam saved Buxton’s effort before Liggett stepped up and netted to secure a resounding 3-0 penalty success.
Belper will now play Woodland LFC in the final at Matlock Town on Sunday April 26.