Worcestershire 128 for 5 (Oliver 70*, Rushworth 2-14) beat Durham 127 for 9 (Ajmal 3-13) by five wickets
Richard Oliver's half-century was the difference as Worcestershire strengthened their grip on second spot in the NatWest T20 Blast North Group by beating Durham by five wickets at New Road.
After losing his place for three games, the former Shropshire captain has bounced back to form with 31 in a win against Nottinghamshire and an unbeaten 70 from 57 balls in seeing off Durham with an over to spare ahead of Friday's meeting with group leaders Birmingham.
Oliver's first T20 fifty for more than a year was just what Worcestershire needed after Daryl Mitchell's early dismissal gave Durham some hope of defending a vulnerable 127 for 9. Tom Kohler-Cadmore and Colin Munro, the latter going for the reverse sweep, followed in quick succession before Brett D'Oliveira made his third significant contribution.
After brilliant work to run out Calum MacLeod and a tight bowling spell, he supported Oliver in a stand of 51 from 6.1 overs. Although his share was a modest 13, it was the match-turning phase before he was bowled by Chris Rushworth.
Oliver made his first move with four fours in an over from John Hastings and in all he found the boundary 11 times, an impressive ratio on a pitch which shackled most of the batsmen. However, he happily took a back seat as Ben Cox finished it off with consecutive fours off Hastings.
In their innings, Durham probably felt they were being picked on by Saeed Ajmal. Having taken 3 for 16 before Worcestershire squeezed home at Chester-le-Street, the Pakistan spinner did a fraction better in ripping the heart out of the Durham batting in five balls.
His intervention came when they were looking to pick up from a reasonable start in which Mark Stoneman, caught at short midwicket for 12, and Macleod fell to tight bowling and smart work in the field.
Paul Collingwood drove one six in an otherwise immaculate stint by D'Oliveira but then picked put Oliver at long-on after a change of ends for Ajmal. With the former England allrounder out for 16, the last thing Durham needed was to lose top-scorer Phil Mustard, but two balls later the left-hander top edged a sweep to short fine leg after clouting successive sixes off Mitchell in making 35 from 37 deliveries.
In his next over, Ajmal choked off the big-hitting threat posed by Hastings. In a repeat of Collingwood's dismissal, the Australian also failed to clear Oliver, although the overhead catch was marginally more difficult.
On a slow surface, the spin pair of Ajmal and D'Oliveira bowled 26 dot balls between them and left-arm paceman Jack Shantry was equally frugal with 14 deliveries without scoring.
His one wicket came when he beat a desperate swing by Usman Arshad as Durham lost four wickets in the last two overs. Gordon Muchall and Ryan Pringle were run out on either side of Arshad's dismissal and Keaton Jennings was bowled by Joe Leach.