Tykes tame Morris men.
With a quarter-final spot already clinched, Durham were rocked by injuries to David Boon, John Morris and Jon Lewis.
Lewis made 67 as Durham struggled to a poor 172 off 50 overs.
Yorkshire's David Byas (52 not out) and Darren Lehmann (65 not out) helped knock off the runs with 15 overs to spare.
Mike Atherton went for a duck as fellow opener Andrew Flintoff cracked 92 in LANCASHIRE'S 258 for eight against NORTHAMPTONSHIRE.
But Lancashire bowled out Northants for 187 to win by 71 runs.