Moeen Ali's first century in the LV= County Championship for nearly two years steered Worcestershire into a strong position in their Division Two clash with local rivals Gloucestershire at New Road.
Having bowled out their neighbours for 234, Worcestershire powered into a lead of 68 when Moeen - badly dropped at mid-off on 99 by Liam Norwell - closed the second day with 122 not out in a total of 302 for three.
While Moeen was all flair and flicks, with 18 fours and three sixes, the diligent Matthew Pardoe grafted for nearly five hours for 89, the highest of seven half-centuries so far in his championship career.
Their partnership of 173 in 52 overs built on the advantage secured by Alan Richardson's opening-day return of 8-37, the best championship bowling for the county since Zaheer Khan took nine wickets against Essex in 2006.
Worcestershire's top order has rarely fired so consistently in recent times but after a sticky period following last year's relegation from Division One, they have been given a shot in the arm by their two-day demolition of Kent last week.
With a first win of the season secured at the fifth attempt, suddenly they are a team playing with authority.
After rain in the morning had cost an hour's play, Gloucestershire's seamers were unable to match Richardson's destructive performance when Daryl Mitchell and Pardoe resumed their overnight partnership of 65.
The first pair moved on to 90 before Mitchell, having hit 10 fours, went for 63, carving a ball from Norwell to Benny Howell at point.
If Gloucestershire hoped this would put them back in the game, they were quickly disappointed as Moeen, always the wristy entertainer, revealed his full repertoire in reaching three figures from 130 balls.
In a partnership of left-handed batsmen, Pardoe had a different role to play and carried it through as Worcestershire would have wanted when pushing him up the order in place of last year's overseas player, Phil Hughes.
Tall and watchful but always quick to punish the bad ball, he hit seven fours in reaching 50 for the second match in a row at New Road and added five more before the new ball gave Gloucestershire a lift late in the day.
In the third over James Fuller bowled Pardoe, and Thilan Samaraweera became a leg-before victim for Craig Miles from the ninth ball he faced.
The final session was twice interrupted by rain and in all 27 overs were lost to the weather.