Veteran seamer Andrew Hall claimed his first five-wicket return of the LV= County Championship season as Northamptonshire edged towards promotion from Division Two by dismissing Worcestershire for 163 at New Road.
The 38-year-old South African hijacked his former country with figures of 5-30, cleaning out their last two wickets in successive balls and helping his current team to three of the five points they need to go up with champions Lancashire.
Worcestershire owed their modest total to half centuries by opener Matt Pardoe and seam bowler Jack Shantry, whose lower-order partnership of 72 in 19 overs was the only serious obstacle as Northamptonshire's bowlers steered their side towards Division One for the first time since 2004.
A first innings score of 250 or more is now all they need to kill off their only rivals, Essex, but this is by no means a formality after closing at 103-4, still 147 short of their target.
Worcestershire bowler Alan Richardson, who was born three months before Hall in 1975, took 2-30 and his dismissal of Stephen Peters (23) secured his 250th championship wicket in four seasons with the Royals.
A day of 14 wickets ended with the spinners in action and there was some turn for Moeen Ali when top scorer Alex Wakeley was leg-before for 35.
Northamptonshire had made the perfect start to the final fixture in an outstanding season in which they captured the Friends Life t20 trophy in August.
By winning the toss Peters was able to give his seamers the opportunity to bowl first on a dank, misty morning.
Straightaway they were in business when David Willey took two wickets with the first four balls of the match and after 43 minutes they had the first bonus point in the bank.
The second arrived before Worcestershire limped into lunch with six wickets down for 72, their top-order having fallen apart around Pardoe.
The left-handed opener has made big strides this season with a maiden century against Glamorgan and now half-centuries in each of the past three games. Although lucky with a couple of edges that failed to carry to the slips, he stayed calm while wickets tumbled.
Willey's opening burst accounted for Daryl Mitchell and Moeen, both leg-before, and with the ball nibbling about, Worcestershire contributed to their own problems when three batsmen were bowled without playing a shot.
Shaaiq Choudhry was the last of these, giving Hall his 600th first-class wicket, but this brought in Shantry to tap the ball around with eight fours and a six in a career-best 55 not out from 74 balls.
Pardoe reached 51 in more than three hours before he dragged his back foot for a neat stumping by David Murphy during 11 overs of spin from James Middlebrook.