After winning the toss and electing to bat first the Northants openers scored at a steady rate with both scoring 30 by the 9th over.
David Willey scored his fifty from 43 balls, including four boundaries and four maximums before he was clean bowled by Blackwell for 57. It was from this point that the Dynamos took control and started pegging back the opposition.
Gareth Breese struck the following over, trapping Alex Wakely, whose fifty came off just 34 balls, lbw for 55 as Northants fell to 119-2 in the 16th over.
The third wicket also fell to spin, this time to Scott Borthwick in his first over, after David Sales (7) was caught by Dale Benkenstein for just 3. The young spinner struck again when he sent Rob Newton back to the pavilion one short of his fifty with Northants 193-4
Graham Onions claimed his only wicket of the match when Rob White (38) sent the ball up high, losing grip of his bat which flew out of his hands, which allowed Mustard to position himself underneath and take with ease.
Paul Collingwood bowled the final over of the day and picked up two successive wickets in the process, that of James Middlebrook who was caught by Will Smith and skipper Andrew Hall who was caught impressively by Ben Stokes.
With 248 the target for the win, Durham accelerated quickly scoring 43 without loss in the first four overs and it wasn’t until they reached 78 that Mark Stoneman was caught by Burton off Hall for 27.
This brought Ben Stokes to the field, who got off the mark with a boundary, with his first stroke, from a free hit.
Some big hitting saw Mustard, taking it in his stride, reach his fifty from just 33 balls which included six fours and two sixes.
Northants would be disappointed with aspects of their fielding but there were glimmers of quality when Rob White held onto a well hit Stokes shot off Willey for 28 with Durham 140-2, requiring a further 108 runs.
Mustard, supported by Collingwood (38* at the end), continued to score freely, reaching his hundred, which included thirteen fours and seven sixes, from just 83 deliveries.
The wicket keeper sealed the win with a huge six to finish the innings unbeaten on 139*.
Durham Dynamos face Surrey Lions in their final group stage match on Monday 29 August at The Kia Oval. Log on to Durham CCC’s Live Match Chat (www.durhamccc.co.uk/live-match-chat) to follow the action as it happens and to show your support!