Lowerhouse made it 15 wins on the bounce as they saw off Rishton on Saturday to set up a titanic tussle with Ramsbottom this weekend.
The West Enders won a rain-effected clash at Blackburn Road by seven wickets, while Ramsbottom cut the deficit to 12 points with a maximum points victory over Rawtenstall.
With five games remaining, the sides meet on Saturday at the Neville Gee Recruitment Ground - although Ramsbottom will have to find a replacement professional after Daryn Smit played his last game of the season on Sunday.
Lowerhouse paid man Cobus Pienaar will also return home next Monday, but will hope to leave his teammates firmly in charge of the title chase, after Sunday’s game at Accrington.
Charlie Cottam won the toss at Rishton and decided to field, with rain expected.
Pienaar took three of the first four wickets to fall to leave the hosts on 64-4, Paul Clifford (1), Afaq Sartaj (15) caught behind, with Nathan Shorrock (0) caught in the slips by Ben Heap, while Matt Walker trapped opener Brad Juliff (3) in front.
Play was halted for rain, but on the restart, Pienaar sent back Matt Leathert (5) lbw and Shaun Hutchinson (4) with a one-handed caught and bowled.
Darrel Thomas was caught by Cottam for 13 off Walker to make it 103-7, but professional Matt Hulett passed his 50, and although he lost Jon Dobson lbw to Pienaar for five, and David Curran (3) run out.
But Hulett denied Lowerhouse the bowling points as he finished on 83 off 111 balls, with Rishton 151-9.
Pienaar took 6-44.
Further rain saw the target reduced to 108 in 30 overs.
Home captain Hutchinson removed Joe Martin (13) lbw, with Jonny Whitehead (30) and Heap (7) both caught, but Pienaar (26 not out) and Joe Hawke (14 not out) saw Lowerhouse to a seven-wicket win off the first ball of the 13th over.