Derbyshire 115 (Riley 4-30) and 32 for 3 trail Kent 333 (Bell-Drummond 101, Palladino 5-62) by 186 runs
Adam Riley and Darren Stevens put Kent on course for their second Division Two victory of the season by demolishing Derbyshire's batting and forcing them to follow on at Canterbury.
Offspinner Riley, touted as an England Test possible against India later this summer, took 4 for 30 as Derbyshire plunged to 115 all out in reply to Kent's first innings of 333. At stumps Derbyshire were 32 for 3 in their second innings, still 186 runs behind at the end of a second day, which had begun with Adam Ball and Robbie Joseph taking their ninth wicket stand to 59 as Kent added 74 runs to their overnight 259 for 8.
Stevens picked up 3 for 25 first time around with his medium-paced seamers. He then took the new ball when Derbyshire batted again to send back opener Paul Borrington in his second over, caught at second slip by Riley, and Stephen Moore lbw for 14 in his seventh over as he tried to pull a ball which kept low.
Brendan Nash, called up to bowl the last over of the day with his occasional left-arm spin, then saw nightwatchman Tom Taylor edge to Stevens at slip as he pushed defensively forward.
Borrington, indeed, fell twice to Stevens in the day. The first time he sliced to Ben Harmison at third slip on 8 soon after lunch, at the start of a Derbyshire collapse which saw them lose eight wickets in the afternoon session and four wickets for three runs in just 21 balls at the height of their slide.
Doug Bollinger, the Australia left-arm fast bowler, also played his part in Derbyshire's demise by dismissing both Moore and Wayne Madsen with the new ball. Moore edged behind on 4, cutting at the fifth ball after lunch, and Madsen was bowled for 7 off an inside edge.
Scott Elstone laboured 26 balls for his nought before becoming the first of Riley's victims on a dry, dusting surface, which was being monitored closely by David Capel, the ECB pitch inspector. Former England allrounder Capel was making a routine visit and had not been summoned by umpires Rob Bailey and Martin Bodenham.
Elstone was caught at slip from a ball that bounced to take his glove, while Alex Hughes and Gareth Cross also failed to score as Derbyshire's first innings fell apart in mid-afternoon. Hughes was brilliantly caught off Stevens by Ball at first slip, left-handed and low down, but Cross looked distraught at being adjudged caught off bat and pad to Riley from the first ball he faced.
Derbyshire were 56 for 7 when Stevens swung one back into the left-handed David Wainwright to have him leg-before for 1 and Marcus North was cleaned up for 18 by an inswinging near-yorker from Joseph just before tea.
Tony Palladino offered 75 minutes' resistance before, on 24, swinging Riley straight to Joseph on the deep midwicket boundary and the biggest partnership of an innings in which 29 extras was the largest contributor came when No. 11 Mark Footitt slogged Riley for a six and a four to make 14 in a stand of 22 with Taylor.
There was also a moment of high comedy when Footitt, stranded and prone in mid-pitch when he slipped trying to turn back in a mix-up with Taylor, escaped a run-out when Kent wicketkeeper Sam Billings could not take an awkward throw. The ball ran away into the outfield and Footitt, who had made no effort to get up as he clearly assumed he was out, scrambled to his feet and ran through for two overthrows.