Premier Division leaders Newark Town fought hard to reach the final of the Willie Hall Memorial Trophy after playing for the last half-hour with nine men.
They overcame First Division underdogs Holy Trinity, who went within a whisker of sending the semi-final into extra-time.
Both teams cancelled each other out in a goalless first-half, with neither able to get on top in an even contest.
The game changed in the 35th minute when Newark’s Sean Fulcher was shown a straight red card after a lunge at striker Ben Ginnelly.
Jason Thurlby went close to scoring at the end of the first-half for Holy Trinity, but his goalbound effort was cleared off the line by Ben Lund.
Holy Trinity took the lead in the 55th minute when keeper Anthony Richardson was ruled to have held a player in the box at a set-piece.
Thurlby buried the spot-kick and Richardson was sent off for dissent after he voiced his displeasure at the decision.
Despite going down to nine men, Newark rallied and laid siege to the Trinity goal, creating several opportunities.
With 20 minutes remaining, Liam Warner levelled when he finished from five yards after good work by Jimmy Rusby and Tom Perkins.
Newark shrugged off the two-man disadvantage and poured forward in search of a winner.
A Perkins free-kick was headed against his own post by a defender before Rusby’s follow-up effort was saved.
But Holy Trinity were unable to hang on as Warner rose highest from a Perkins free-kick to head past the keeper.
Holy Trinity hit the woodwork in the final seconds after a hectic goalmouth scramble, but they could not turn the ball over the line to force extra-time.
Newark Town will face First Division Witham Wanderers in the final.
Wanderers knocked out a side from a higher league for the third time this season, beating Barkestone-le-Vale 4-1.
Wanderers, who have improved in recent weeks, previously overcame Newark Flowserve and Coddington Mill.
Barkestone made the better start and took an early lead from Richard Bishop’s excellent finish.
That sparked Wanderers into life and they equalised with five minutes of the first-half remaining through Scott Lloyd, who finished smartly past the keeper.
A second goal was added before the break when Adam Mella fired low into the corner.
Barkestone came out strongly in the second-half but could not force an equaliser as the Witham keeper made excellent saves.
Stuart Garner went closest to scoring when his effort was tipped on to the post.
Witham, dangerous on the counter-attack, edged into a 3-1 lead with a superb finish from Jamie Kightly.
The win was completed by Wayne Martini, who converted from 20 yards to seal a place in the final in their first season in the league.
The final will be held on May 20 at Newark Flowserve.