The Division Two title challengers were at home to Netherton United from Division One in Sunday’s semi-finals and they edged through 4-3 thanks to a Leland Dent hat-trick and an own goal .
Taking their place alongside them in the final will be Spalding United Blue from Division One.
They overcame Pinchbeck United from Division Two 6-1 thanks to two goals each from Ben Greenacre and Derrie Maxwell and one apiece for Zak Lindsay and Keane Slayven.
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Glinton and Northborough Navy Under 12s were crowned Division Five champions on Sunday.
A 4-2 win at Boston United Ladies thanks to goals by Devonte Malachi Butler, Takunda Fashitudu, Charlie Shingles and Jack Yeardley put them beyond the reach of Wittering Harriers, who were the only side that could stop them.
Wittering beat ICA Sports 5-0 to claim the runners-up spot. Archie Lamont and Ben Skellett both bagged a brace.
It was goals galore in Under 12 Division Three with Parkside Blue 8-0 winners against Deeping Rangers Clarets and Netherton Falcons beating Park Farm Pumas Red 7-3.
Sami Belrhazy and Muhammed Harris fired doubles for Netherton.
Bretton North End picked up only their second win of the season in Under 12 Division Four when beating Oundle Town 3-0 with goals by Liam Jones, Leon Cruddace and Arnez Harrison.
In Under 12 Division One, Crowland narrowed the gap on table-toppers Stamford Reds to five points with a 6-0 victory over Colsterworth Colts. Both teams have four games left to play.
Crowland’s scorers were Harleigh Camfield (2), Teddy Hill (2), Samuel Smith and Matas Sakavicius.
Oundle Town Under 14s moved to the top of Division Two in a big way.
They smashed Stanground Sports 8-1 with Cameron Clark and James Aubury both hitting hat-tricks.
Oundle have a two-point lead over Boston United Community FC but the Lincolnshire side have two games in hand.
Oundle Town reached the Under 18 League Cup final in emphatic fashion on Sunday.
They beat lower level Glinton and Northborough Navy 4-0 and will now meet Gunthorpe Harriers Navy from Division Two in the final at Yaxley FC on Thursday March 21 (7.30pm).
The Under 15 League Cup final between FC United Hammers and Holbeach takes place at Yaxley FC tonight (March 14, 7.30pm) while the Under 16 decider took place last Thursday.
That resulted in a 6-1 win for Division One champions-elect Stewart & Lloyds against Yaxley.
Hampton Blue look set to finish as runners-up to JFC Boston in Under 15 Division Three after a 5-0 win over Rippingale & Folkingham on Sunday.
Alfie Richardson (2), Benjamin Atkinson, Flynn Harrison and Mohammed Rohman got the goals and Hampton need to win just one of their two remaining fixtures to take second place.
Thurlby Tigers moved up to third place in Under 18 Division Two by beating winless Hungate 8-2 with goals by Thomas Chaytor (2), Angus Manning (2) Searaj Abuzoda, Alfie Smith, Milan Spasojevic and Luke Toomey.