Joe Clarke achieved his career best score and Joe Leach a first century for three years as Worcestershire put the Derbyshire attack to the sword on day two of the Specsavers County Championship clash at New Road.
Clarke and Leach put on 157 in 32 overs – a Worcestershire record for the seventh wicket in matches against Derbyshire – as the home side amassed 475-7 declared.
Worcestershire plundered 220 runs in 45 overs after resuming on 255-6 before the declaration in mid afternoon.
Clarke, who was on 117 overnight, went onto make 194 as he surpassed his previous best tally of 135 against Gloucestershire at Bristol earlier this summer.
The England Lions player was eventually dismissed in the final over before lunch, caught at deep mid wicket off Wayne Madsen.
Clarke struck one six and 25 fours in his 328 ball knock.
Leach went to his hundred off 138 balls with 12 boundaries via a four through mid wicket off Tony Palladino shortly before the declaration.
West Indies paceman Miguel Cummins took the new ball and his third delivery almost accounted for Ben Slater who survived a chance at fine leg.
But a combination of rain and bad light meant Derbyshire only faced 2.3 overs in short spells before tea was taken at 3.30pm.