Worcestershire 363 (D'Oliveira 93, Cox 56*, Barnard 46) and 295 for 8 dec (Mitchell 130) beat Gloucestershire 258 (Taylor 101*, Barnard 4-23) and 211 (Ashwin 5-68) by 189 runs
Indian spinner R Ashwin took five second-innings wicket to ensure a winning debut as Worcestershire climbed back into the second promotion spot in the Specsavers County Championship with a 189 run success over Gloucestershire at New Road.
Ashwin, having a brief taste of county cricket ahead of India's tour next year, completed a productive opening game for his adopted county by taking eight wickets in total - including 5 for 68 in the second innings - and making useful contributions with the bat.
He left the outfield to a standing ovation proudly displaying the match ball.
Worcestershire's sixth Championship win of the campaign moved them 19 points clear of Sussex, who have a game in hand as Gloucestershire were dismissed for 211.
They will head into next week's top of the table clash with leaders Nottinghamshire at Trent Bridge full of confidence after this comprehensive victory against their neighbours from down the M5.
It was a welcome return to form for the home side after a disappointing NatWest T20 Blast campaign and defeat against Sussex in their last Championship match at New Road.
The majority of their batsman made sizeable contributions and Ashwin was well supported on a used pitch that might have been designed for him by Worcestershire's seam attack in which Ed Barnard was again outstanding.
Gareth Roderick, skipper Phil Mustard and first innings century-maker Jack Taylor all got into the 40s for mid-table Gloucestershire but their resistance was ended in mid-afternoon by Ashwin and co.
Gloucestershire resumed on 55 for 3 and Ashwin came straight into the attack for the second over of the morning and, apart from a brief spell by Brett D'Oliveira, bowled from the New Road End for the majority of the day.
It was Barnard who made the first breakthrough as nightwatchman Tom Smith (9) was trapped lbw by a delivery which ket low.
Ashwin collected his third wicket of the innings in the next over as George Hankins also fell leg before for a duck.
Gareth Roderick and Mustard defied Worcestershire for 13 overs.
Worcestershire skipper Joe Leach brought himself into the attack and knocked back the middle stump of Roderick for 47 - his 49th Championship victim of 2017.
Mustard and Taylor provided stiff resistance during a partnership of 71 in 18 overs but the contest was effectively ended when they both departed in quick succession. Mustard (40) presented Leach with a comfortable catch at mid off when facing rookie paceman Pat Brown and Taylor (43) fell leg before to Ashwin who completed his nap hand when Kieran Noema-Barnett was caught at fine leg.
Leach rounded off Worcestershire's victory by bowling Liam Norwell to secure his 50th Championship wicket of the campaign.