Farthingstone gave themselves a great chance of qualifying for the last four after recording a 3-2 victory at Stoke Albany. Cold Ashby and Collingtree, who travel to Farthingstone for their last game, now sit joint-top with two wins out of three matches.
Kingsthorpe will not be able to qualify for the semi-finals, despite ending their campaign on a high with a 4-1 home success against Priors Hall.
Needing a whitewash win to have any chance of topping the group, a narrow victory for away duo Ian Abrahams and Paul Freeman in game two meant Wellingborough and Silverstone will battle it out for a place in the last four.
With no team having recorded an away in this section, Wellingborough are strong favourites to progress as they just need to take just one tie at Silverstone next month to finish first on points difference.
Oundle completed their campaign with a 4-1 home win as they defeated Whittlebury Park, whose only success came from David Melling and Anthony Broadbelt. Daventry recorded a 4-1 home victory against Peterborough Milton.