Mark Footitt dismissed Gloucestershire’s Hamish Marshall and James Fuller in successive overs to keep Derbyshire on course for victory in the LV= County Championship Division Two match at Bristol.
Gloucestershire resumed on 253 for six, still 17 in arrears, and Marshall and Fuller frustrated the visitors for most of the morning session.
However, their seventh-wicket stand of 94 was broken in the 107th over when Fuller, who had hit nine boundaries in a fluent 51, was bowled by an inswinging Footitt delivery.
The left-arm seamer struck again in his next over from the Pavilion End when Marshall fell victim to a third brilliant, one-handed catch of the innings by fellow New Zealander Martin Guptill, who plucked his square drive out of the air above his head at point. Marshall had batted more than four hours for his 79, which included 10 fours.
Craig Miles and Liam Norwell were on 12 and four, respectively, at lunch, with Gloucestershire on 379 for eight, a lead of 109.