Ian Westwood completed his century but Warwickshire faltered slightly on day three of their LV= County Championship Division One clash against Middlesex at Uxbridge.
Jim Troughton failed to add to his overnight score of 60 after he was caught behind off Gareth Berg before Westwood brought up three figures off 270 deliveries.
He became Tim Murtagh's third victim after adding 11 more runs and Steven Crook snared Darren Maddy as Warwickshire went to lunch on 251 for five - still trailing by 162 runs.
Lancashire slumped to 72 for six and their hopes of setting a formidable chase for Somerset would appear to hinge on Ashwell Prince at Aigburth.
The left-hander was unbeaten on 27, with only Steven Croft (13) the only other batsman from their top order to reach double figures as Lancashire extended their lead to 108.
Alfonso Thomas was the pick of the bowlers with two for 19 but the Red Rose contributed to their own downfall as Stephen Moore and Gareth Cross were both run out.
There was no play before lunch at Hove, where Sussex were looking to build their lead of 163 after closing on 325 for seven last night.