Worcestershire set Durham a 291 target and went down fighting to the end by three wickets on the final day of the LV = County Championship match at the ICG Emirates.
Worcestershire resumed on 42-0 and plundered 175 runs in the morning session from just 25 overs before declaring on 217-9 and leaving themselves 71 overs to bowl out the home side.
A fine 99 from Scott Borthwick enabled Durham to launch a strong reply but Worcestershire kept chipping away and picking up wickets at regular intervals to keep themselves in the contest right to its tense conclusion.
An unbeaten half century by Michael Richardson edged Durham home and meant that Worcestershire were relegated after one season back in the top flight.
They were left to reflect on what might have been without the loss of day two to rain which forced their hand and meant they had to set a less formidable target because of the need to push for a victory today.
But Worcestershire can be proud of having given every ounce of effort and commitment – and at times producing some excellent cricket – before their fate was confirmed.
Now, with their crop of young players signed up on a long term basis, the County will now look to bounce back strongly in 2016 after the curtain comes down on the season against Middlesex at New Road next week.
Worcestershire openers Daryl Mitchell and Brett D'Oliveira extended their stand to 68 before three wickets fell for four runs.
Chris Rushworth took his 100th wicket of the season in county cricket – 83 of which have come in the County Championship when he bowled Mitchell for 21.
Then Graham Onions bowled D'Oliveira when one short of his maiden Championship 50 – after he had hit eight fours in his 56 ball knock – and dismissed Joe Clarke for a second ball duck.
But Tom Fell hit three fours in an over from Rushworth in making a quickfire 28 and Tom Kohler-Cadmore and Ross Whiteley figured in a rapid stand of 69.
Onions conceded 16 runs in the final over his nine over spell.
Whiteley picked up Jamie Harrison behind square for six and Tom Kohler-Cadmore cleared the rope off Ryan Pringle before holing out at deep mid-wicket for 38 off 41 balls.
Ben Cox scored his six runs in one blow off Scott Borthwick before falling lbw to the leg-spinner attempting a reverse sweep.
Whiteley made his 47 off just 21 balls with eight fours and a six before he drove to long-off and Pringle picked up a third wicket when Ed Barnard was lbw for 17, prompting the declaration at 217-9.
When Durham began their reply, Shannon Gabriel struck in his first over – and the second of the innings.
The West Indian paceman trapped Jack Burnham lbw for one to claim his first wicket for the County.
Borthwick and Mark Stoneman added 75 in 20 overs before the latter on 28 was caught at cover by D'Oliveira off Jack Shantry.
Shantry caused problems for Borthwick who just evaded leg slip on 30 and edged just short of first slip when on 40 before reaching his 50 off 70 balls.
Paul Collingwood joined Borthwick and the pair took Durham through to 119-2 with one session remaining.
Their stand was worth 104 in 23 overs when Borthwick on 99 aimed a pull at D'Oliveira and was trapped lbw. He hit 15 fours in his 121 ball knock.
Gabriel returned to the attack and a ball of full length swung and was edged by Collingwood (47) to keeper Cox at 215-4.
Cox then took a fine catch to dismiss Gordon Muchall (12) off Barnard and it became 266-6 when Ryan Pringle (9) was caught by Barnard off Joe Leach.
Mitchell brought D'Oliveira back into the attack and he had Jamie Harrison (1) lbw before Richardson saw Durham home with 4.2 overs to spare.