Captain Coral Handley guided Worcestershire to the LV C County Women's Championship Division Three title with a win a main rivals Devon.
The County started the day at Plympton CC 15 point behind Devon in second place knowing a good victory would be enough.
Worcestershire had to restrict their hosts, who elected to bat first, to four bonus points for less and wanted to keep them below 150 runs.
Devon managed 153 all out with a half century seventh wicket partnership. They made a solid start with a run-rate of more than four an over, but the first breakthrough was made by skipper Handley.
She brought mid -off in close and then took the wicket of Olivia Anderson to Kate Blunt's catch.
Devon were reduced to 61-2 after Rachel Baldwin took an inspired catch off Jo Greaves' bowling. Thea Brookes claimed the wicket of potential match winner Heather Knight (34).
Devon slumped to 67-6 as Naomi Heywood ran out captain Lottie Miles for a duck while Brookes and Ellen Smith claimed further victims.
Amara Carr (43 not out) and Jo Dibble (21) revived Devon before Charlotte Holtom intervened.
Two more wickets from Holtom restricted the home side further before Handley finished the job in the final over as Devon claimed two batting bonus points.
Worcestershire needed to lose just six or less wickets in t heir run-chase or victory would not be enough for the tile and promotion.
Devon conceded a string of extras and the visitors recovered from an early wicket through Brookes and Blunt (19). Heywood and Brookes took the county past 100 runs before a borderline decision dismissed the former.
Brookes was unlucky to be dismissed lbw for a fine 62 but Claire Boycott (15no) and Handley led Worcestershire to victory.
With four overs to spare, Devon's 30th wide sealed their fate.