Durham 218 for 5 (Mustard 91) beat Lancashire 216 for 9 (Rushworth 3-44) by five wickets
Phil Mustard's aggressive 91 saw Durham race to a notable Yorkshire Bank 40 win over last season's semi-finalists Lancashire. It was Durham's first List A win at Old Trafford.
In pursuit of 217 to win, Mustard and opening partner Mark Stoneman scored at 10 runs an over in the Powerplay - including a run of 26 runs off seven balls. Stoneman hit Wayne White for five fours in the fourth over before Mustard pulled Oliver Newby for six at the start of the fifth.
But, after the departures of Stoneman for 32 and Ryan Pringle in the space of eight balls to leave the score at 81 for 2 in the ninth over, Mustard built upon the early assault to secure a first win at the second attempt with 31 balls to spare.
Lancashire, who posted 216 for 9, got off to a flyer in their first outing thanks to openers Stephen Moore and Ashwell Prince in a 73-run stand inside 11 overs. Moore, who has not been able to force his way into his county's early-season County Championship plans, led the way with 46 off 37 balls, even pulling Mark Wood for a six over square-leg as Lancashire passed 50 in the early stages of the eighth over.
But Prince, for 34, and Moore both fell inside four overs to Gareth Breese and Ben Stokes to leave the score at 83 for 2. From then on, Lancashire could not maintain the same intensity as their innings stumbled along with the loss of regular wickets.
Karl Brown hit 32 before being stumped by Mustard off Pringle's off-spin - the same way Prince had fallen to Breese. And when stand-in captain Simon Katich was caught behind off Wood, the hosts were 128 for 5 in the 26th over. Jordan Clark and White tried their best to up the ante but, despite the latter's 37 off 47, they were unable to do so.
Chris Rushworth nipped in with three of the last four Lancashire wickets to fall - those of Clark caught at long-on, White caught and bowled and Newby caught behind - to finish with 3 for 44.
After Mustard and Stoneman shared 71 inside seven overs, the former added 90 inside 17 with Paul Collingwood for the third wicket. Mustard hit eight fours and two sixes over midwicket in 86 balls having been dropped on 43 by Simon Kerrigan.