Openers Lumb and Adams paved the way to Hampshire's 64-run victory
Hampshire booked their place in the Friends Provident Trophy final with a 64-run win at Old Trafford which kept up Lancashire's semi-final nightmare.
After being put in, Hampshire booked a place at Lord's against Sussex on 25 July thanks to an 159-run opening stand between Michael Lumb and Jimmy Adams.
The Hawks collapsed to 271 after Adams (78) and Lumb (76) were out.
But after Adams' superb catch removed VVS Laxman (54), the hosts were never in the hunt and were all out for 207.
Hampshire, who last won English cricket's premier one-day trophy when they lifted the Cheltenham and Gloucester Trophy in 2005, are back at Lord's for the first time since being hammered by Durham in the 2007 FP Trophy final.
But, for Lancashire, it was an extension of their miserable run in semi-finals.
They did make the last C&G Trophy final in 2006, losing to a Sussex side led by Peter Moores. But this is now the ninth time they have fallen at the last four hurdle in a competition since winning their last trophy, the Axa and Equity League in 1999.
And, with Sussex having booked their latest return to Lord's thanks to a 34-run win over Gloucestershire in the other semi, that meant Moores missing out on a reunion against his old Sussex employers.
After Lancashire's fateful decision to field first, Hampshire wasted little time making them pay. And they looked on course for a massive total when openers Lumb and Adams reached halfway on 159-0 off 25 overs.
But then 10 wickets went down in 24 overs for only a further 112 runs as Lancashire skipper Glen Chapple, Gary Keedy and Sajid Mahmood claimed three wickets apiece.
The opening stand had contained 12 fours and three sixes but there were only four boundaries in the remainder of the Hampshire innings.
Lancashire were already labouring even before Adams' double return to centre stage.
Hampshire skipper Dimitri Mascarenhas struck with his first ball when opener Paul Horton edged to Lumb at slip.
And, although Mal Loye looked in decent nick, adding 73 in 14 overs with Laxman, he missed an attempted sweep at spinner Imran Tahir to fall lbw for 31.
That became 108-3 when Mark Chilton perished on the mid-wicket boundary for 18. And then came Adams' double contribution in the field to effectively end the contest.
A one-handed catch at backward point off Sean Ervine got rid of Francois du Plessis before Adams then held on to Laxman's powerful drive to short extra cover. And Tahir (3-38) worked his way through the tail.
Hampshire cricket manager Giles White told BBC Radio Solent:
"I'm over the moon for the lads. They've put in a great performance.
"History says over the years that 270 here would be a winning score.
"Sussex are big rivals. We always like to beat them. Hopefully it will be a big crowd there and a good day out."
Hampshire bowler Liam Dawson told BBC Radio Solent:
"Words can't describe it. To come here and win at Old Trafford is unbelievable.
"It gives me a lot of confidence having bowled well here.
"We're still in the mixer for all three competitions and hopefully come September that will still be the case."
Lancashire wicket-keeper Luke Sutton told BBC Radio Manchester:
"I don't think we can have any complaints. We were outplayed and beaten by the better side.
"271 was still a gettable score. We've chased down some big scores this season which is why we chose to chase.
"We were always a little below the rate. And we kept losing wickets at key times. But, in the end, we just weren't good enough."
Lancashire coach Peter Moores told BBC Radio Manchester:
"I've always said you have 24 hours to celebrate a win and 24 hours to mourn a defeat. Now we just have to concentrate on the Championship game with Worcestershire on Friday.
"All credit to the way Jimmy Adams and Michael Lumb came out and put us under any pressure. We did well to limit them to what we did as at one stage it looked more like 330 or 340.
"But they then bowled well, we didn't bat as well as we could do. And it was a couple of great catches by Adams."
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