Derbyshire 338 (Godleman 51, Reece 51, Wiese 4-63, Garton 3-79) and 322 for 8 (Podmore 66*, Whittingham 5-80) lead Sussex 271 (Wright 70*, Viljoen 7-80) by 389 runs
Derbyshire put themselves in a position to claim only their second win of the season in the Specsavers County Championship after an attritional third day against Sussex at Hove.
They closed on 322 for 8, a lead of 389 against a Sussex side who will be obliged to chase any target on the final day for a victory to keep their slim promotion hopes alive.
It has been a collective effort by the Derbyshire batsmen with nine players scoring between 38 and 66 in the match. They included Middlesex loanee Harry Podmore, whose previous highest score was 21 but who was unbeaten on 66 at stumps from 117 balls. He hit five fours and a six off George Garton in the final over.
Derbyshire's run rate never got much above four an over throughout the day but, having resumed with a lead of 108 and nine wickets in hand, they did not need to take risks.
Sussex kept at it but with their spearhead Jofra Archer showing the effects of a long season and struggling for full pace and a slow pitch blunting the efforts of the rest of their seam attack the hosts had to work hard for their wickets.
The big positive for Sussex was Derby-born Stuart Whittingham, who claimed his maiden five-wicket haul in only his third Championship appearance of the season. Whittingham bowled with real venom at times and the yorker which speared into Ben Slater's stumps after the opener had made 45 would have been too good for most batsmen.
After lunch Whittingham, who took eight wickets in two games against Derbyshire last season, persuaded Matt Critchley, who played the most fluent strokes of the day in his 51, to pull into the hands of deep mid-wicket when the bowler dropped short before taking two wickets with the second new ball.
Harvey Hosein demonstrated plenty of resolve but shortly after reaching a 111-ball half-century - one of five in the match by Derbyshire batsmen - with four boundaries before he sliced a full-length ball to backward point.
Hardus Viljoen was yorked by Whittingham, who had Will Davis caught at mid-wicket for 25 in the penultimate over. But the ease with which Podmore batted suggests that Sussex's batsmen could be in business on the final day.
With the pitch offering little assistance and no spinner in their attack to offer any variety, it was hard work for the home attack, Whittingham apart. Ollie Robinson was rewarded for a good opening spell when Wayne Madsen shuffled in front for 31 while a toe-crushing yorker from Garton was too good for Alex Hughes in the second over after lunch.