Worcestershire all-rounder Joe Leach produced another impressive performance with the ball as Derbyshire were forced to follow on in the Specsavers County Championship clash at New Road.
Leach followed up yesterday's century with his fifth five wicket haul of the campaign as Derbyshire were bowled out for 248.
Only century-maker Harvey Hosein and Championship debutant Greg Cork (49) provided prolonged resistance as the Peakites followed on 227 in arrears.
Then Leach struck an early blow in Derbyshire's second innings to remove Ben Slater as the visitors closed on 15-1.
Leach has now taken 64 Championship wickets to surpass last year's previous best tally of 59 in addition to scoring more than 600 runs in the competition.
But it was a disciplined and concentrated effort from the entire attack on a still slow and flattish pitch where making use of the new ball is crucial.
Derbyshire resumed on 15-0 and were immediately on the back foot after Leach removed Billy Godleman and Tom Wood in the space of five balls.
He had Godleman (11) caught behind – an excellent take by Ben Cox diving away to his left – and trapped Wood (0) lbw in the same over.
Miguel Cummins worked up a good head of pace and had Wayne Madsen lbw (5) before Charlie Morris made a double breakthrough.
Slater (25) edged through to Tom Kohler-Cadmore at first slip and the same combination accounted for Alex Hughes (4) and it became 103-6 shortly after lunch when Tom Milnes (16) was caught behind.
Cork, son of former England all-rounder Dominic Cork, joined Hosein to frustrate the Worcestershire attack for 33 overs during a seventh wicket stand of 96.
Hosein showed more of his potential with the bat after scores of 52 not out against Gloucestershire and 83 not out and 58 versus Leicestershire in his previous three knocks.
Cork was denied his maiden 50 when he pulled Leach into the hands of Joe Clarke in front of square.
Hosein's march towards three figures was threatened when Ed Barnard trapped Tony Palladino (8) lbw and bowled Will Davis (0) with successive deliveries.
He then survived a run out scare on 97 before going to his hundred and reached 108 before Leach claimed his fifth wicket.
Slater (0) departed for the second time in the day when he clipped Leach to Tom Fell at mid wicket.