Lancashire and Essex both failed to reach the Yorkshire Bank 40 semi-finals after the visitors won a high-scoring contest by 70 runs at Emirates Old Trafford.
A superb 130 for England limited overs batsman Ravi Bopara underpinned the Eagles' imposing 297-4, which the Lightning responded to with 227 all out inside 37 overs.
Tom Smith hit an excellent 84-ball 97 but the home side's task was too stiff. Tim Phillips nipped in with 5-42 from 7.4 overs as Lancashire lost their last eight wickets for 41 runs, slipping from 186-2.
Bopara warmed up for England's two-match Twenty20 series against Australia later this week with his highest List A county score since June 2008, including nine fours and three sixes in 102 balls.
After James Foster elected to bat, Bopara and Greg Smith ensured an impressive recovery from the early loss of India international Gautam Gambhir as they shared 159 inside 23 overs for the second wicket.
Bopara hit Ashes-winning left-arm spinner Simon Kerrigan, who was playing in the fifth Test at the Oval 24 hours earlier, for six over long-on in the 18th over before hitting off-spinner Steven Croft straight down the ground for his second maximum.
He later hit his third off Kabir Ali over square-leg, taking 22 off the former England man in the 36th over of the innings having brought up a 91-ball ton just two overs earlier.
After Kerrigan had Smith stumped for 78 off 77 balls, Bopara shared 61 in 5.1 overs for the fourth wicket with Ryan ten Doeschate before he top-edged Kyle Hogg to short third-man in the search for quick runs.
Ten Doeschate also hit three sixes in 46 not out off 23, helping to take 76 runs off the last six overs.
Smith and Stephen Moore gave Lancashire a good platform with an opening stand of 79 in 11 overs for the first wicket, and despite Reece Topley getting Moore caught at long-leg and bowling Ashwell Prince inside four overs, the hosts had wickets in hand.
An accumulative partnership of 95 inside 15 overs for the third wicket between Smith and Paul Horton kept Lancashire in the hunt.
But when Smith was bowled by Topley to leave the score at 186 for three after 29 overs, things started to go downhill quickly.
Phillips had Horton, Croft, Karl Brown, Arron Lilley and Kerrigan all caught playing expansively. Horton was brilliantly caught by a diving Bopara running towards the sight-screen from long-on to start the run of wickets.