Thornhill Lees require just five points from their remaining three matches to clinch the Heavy Woollen Sunday League Premier Division title.
Lees overcame Woodman Batley Carr 2-1 on Tuesday to move within four points of leaders Birkenshaw, who have finished their programme.
Lees won their derby against Overthorpe Sports Club 2-0 last Sunday.
Lees had goalkeeper Liam Ward to thank for denying Overthorpe early on before Joel Clegg volleyed the visitors ahead.
Just after half-time James Wilson’s speculative shot deceived Overthorpe goalkeeper Michael Williams and squirmed into the net.
Williams redeemed himself by saving well from Scott Hargreaves as Lees hung on for the points.
Lees meet Woodkirk Valley in the Brook Butler Cup semi-final at Beck Lane this Sundaty and then face third place St John Fisher in the league next Tuesday.
AFC Chickenley guaranteed their safety as they beat bottom side Mirfield Town 5-3.
Shaun McDaid (brace), Tim Clarke, Michael Chadwick and Sean Housecroft netted for Chickenley.
Gibril Bojang (two) and Michael Rounding replied for Mirfield, who need to win their final two games to have any chance of staying up.
St John Fisher Reserves enjoyed a 5-0 win over the Championship’s bottom club Hartshead as a double from Chris Thornton, plus strikes from Dominic Simpson, Lee Wood plus an own goal sees Fisher finish mid-table, with Hartshead joining Gomersal in Division One next season.
White Horse climbed to second place in Division One last Sunday after Dale Joy (brace), Jamie Pearson and Brian Bradshaw all netted in a 4-3 win over Batley Irish Nash.
Having completed all their fixtures, White Horse must wait to see if Mount Pleasant can pinch the runners-up spot in their final game with Saville Arms.
Woodkirk Valley completed their Division Two season with a 100 per cent record after winning 6-2 at St Ignatius, who had Robert Smith and Bunn Darboe on target.
Woodkirk have completed the double after also winning the Heavy Woollen Challenge Trophy and now face Premier giants Thornhill Lees in the Brook Butler semi this Sunday.
Punch Bowl ensured they will finish third after hammering Overthorpe Sports Club Reserves 9-2.
Nathan Clarke led the way with four goals, Josh Wood hit a brace, with Dean Brown, Liam Roadnight and Kyle Kershaw completing the tally.
Sean Hodgson and Danny Marshall replied for Overthorpe.
Clifton Rangers finished runners-up and are promoted with Woodkirk after extending their advantage over Punch Bowl to seven points with a 3-0 win at St Ignatius on Tuesday.
Overthorpe Sports Reserves and Black Horse finish fourth and fifth respectively after batting out a 2-2 draw in their final games of the season on Tuesday.
Town Rangers clinched the HDivision Three title with a 2-1 victory over Hanging Heaton CC in a feisty encounter on Tuesday.
Town took an early lead but leading scorer Dave Hall levelled for Heaton with his 20th goal of the season after some neat play down the right.
Town regained the lead after the break but looked nervy with the title in sight and Heaton created a host of chances, the best of which saw James Byrne almost grab a second equaliser when a dipping 30-yard effort in injury time was tipped over.
The sides meet again on Sunday but Town are champions, meaning Dewsbury West Side finish runners-up and Heaton third.
Town won 6-1 at Black Horse Reserves (Adam Gibson) last Sunday to move within touching distance of the crown.
West Side beat Cobras 4-3 and Heaton overcame Gomersal West 7-4 with Hall and Craig Stephenson among their goalscorers.