Lancashire 157 for 8 (Livingstone 44, Davies 31) beat Derbyshire 145 for 7 (Madsen 34, MacLeod 30, Lester 4-25) by 12 runs
Lancashire claimed a 12-run victory in a low-scoring Vitality Blast clash with Derbyshire at Emirates Old Trafford to register their third successive win in North Group
The Lightning posted 157 for 8, with captain and opener Liam Livingstone's 44 off 21 balls the highlight, before the Falcons failed to get 18 off the last over and finished on 145 for 7.
Lancashire would have had higher expectations at 68 for none in the sixth over but subsided as leg-spinner Matt Critchley, medium pacer Alex Hughes and overseas seamer Wahab Riaz (two for 20 from four overs) claimed two wickets apiece.
The Falcons, who have now lost four from four in the North Group, providing a headache for their specialist T20 coach John Wright, were 81 for 2 late in the 10th over of their chase before being shackled on a tired surface.
Leg-spinner Matthew Parkinson was excellent with 2 for 21 from four, while fledgling left-arm seamer Toby Lester returned a career best 4 for 25 from four.
Livingstone and Alex Davies, who hit 31, shared an opening stand of 160 in last Friday's away win over Derbyshire and blazed away here.
Livingstone backed up his maiden century in that match with some more vicious hitting.
He smashed two sixes, including one arrow straight off Lockie Ferguson which thudded into a pavilion window.
The Red Rose skipper then fell to a smart low catch at long-on from Wayne Madsen off the medium pace of Hughes with the final ball of the power play. Hughes later had Davies caught at short third-man reverse sweeping.
Critchley and fellow leg-spinner Matty McKiernan - both playing against their home county and the latter on debut - contributed to Lancashire's slump.
Critchley claimed two wickets in his two overs, while McKiernan bowled four cheap overs. Left-armer Riaz bowled Lester and had Steven Croft caught behind late on.
Lester, with variations aplenty, then struck in the first over of Derbyshire's chase to get Ben Slater caught at cover before removing pinch-hitting Pakistani, Riaz, caught behind in the fifth.
That brought key man Madsen to the crease, who busily advanced the Falcons alongside opener Calum MacLeod (30) as they reached their 50 partnership in five overs. But three balls later, MacLeod was stumped down leg by Dane Vilas off Jennings' medium pace, leaving the score at 81 for 3 at halfway.
Parkinson had Madsen caught behind off a top-edge for 34 and Gary Wilson caught at deep mid-wicket in the 13th and 15th overs, leaving the score at 96 for five.
Daryn Smit and Critchley then revived Derbyshire hopes and took the target down to 23 off the last two before James Faulkner conceded only five off the penultimate, leaving Lester with room for manoeuvre in the last.
He even had Critchley and Smit caught in the deep with successive deliveries in only his third match.