Captain Ben Simm won the toss and decided to put the home side into bat firstand from their 40 overs they amassed 162 runs for the loss of just six wickets.
However, Lancaster made a superb start and reduced Penwortham to 7-2 as Liam Moffat (2-44) got rid of Ian Walmsley (4), Jamie Heywood taking the catch, while Charlie Swarbrick (2-21) got rid of Jack Aspden (1).
Kane Donaghy (8) was next to go when he was bowled by Swarbrick with the score on 42, but Martyn Brierley (62) and Glynn Parkinson (27) helped rebuild the innings.
Parkinson eventually fell, Kieran Moffat (1-26) taking his only wicket of the day with the help of Lee Sparks, and Declan Billington then came and went without scoring, Simm (3-41) taking his first wicket of the day, as Penwortham were left on 96-5.
Brierley’s impressive innings came to an end when he was out LBW to Simm, and Sam Ryding (15) was out LBW to Liam Moffat as the hosts appeared to be struggling on 131-7. It was soon 131-8 when captain Ashley Billington (13) was caught off the bowling of Simm, but Penwortham rallied and managed to finish on 162-8.
In reply, Jamie Heywood (5) was caught by Jack Aspden off Jon Roebuck (4-27), Swarbrick (7) was caught by Ian Stopford, again off Roebuck, and the Penwortham bowler also removed Steven Fisher(16), who was caught by David Crabtree, leaving Lancaster on 44-3.
Nathan Whitehead (28) was caught by Brierley off Roebuck and Kieran Moffat (28) was bowled by Billington (1-53), while Laurie Atkinson (44) was caught by Ashley Billington off Ryding, but Lancaster reached their target after 29 overs to stay top of the table.