Gloucestershire reduced the hosts to 28 for 3 in their second innings but du Plooy's 61 off 77 balls guided Derbyshire to 166 for 5 to secure the draw
Derby (fourth day of four): Derbyshire 251-9d & 166-5, Gloucestershire 383 - Match drawn
Derbyshire captain Leus du Plooy steered his side to safety with an unbeaten half-century on the final day of the LV= Insurance County Championship match against Gloucestershire.
Gloucestershire were in with a chance of victory when Derbyshire slipped to 28 for 3 but du Plooy's 61 off 77 balls guided Derbyshire to 166 for 5 to secure the draw.
The visitors claimed their first batting points of the season before being bowled out for 383, a lead of 132, with Ben Charlesworth, Zahar Gohar and Matt Taylor scoring fifties.
Gohar and Taylor shared a ninth wicket stand of 99, a Gloucestershire record against Derbyshire, to set up the prospect of a tense finale but du Plooy stood firm.
Any late drama looked unlikely at the start when Gloucestershire's main objective was to secure batting points.
Wickets for Ajeet Singh Dale had Derbyshire in trouble (Harry Trump/Getty Images)
Charlesworth was also eying a maiden first-class century and with Tom Price, carried his side to within five runs of 250 when Derbyshire broke the partnership.
Price had already been dropped twice, at short midwicket off Suranga Lakmal and a caught and bowled chance to Alex Thomson, before he went for a big swing at the off-spinner and miscued to cover.
The pair had put on 63 from 129 balls and Charlesworth, who had passed his previous best score of 77 not out, secured the first point when he cut Henry Brookes over the slips for four.
Charlesworth was caught behind off a short ball from Brookes and Marchant De Lange’s attempts to hit the ball out of the Incora County Ground resulted in a broken bat before he edged Lakmal to second slip
But that was the home side's last success for 18 overs as Taylor and Gohar eclipsed Gloucestershire’s highest ninth-wicket stand against Derbyshire of 95 by Mark Hardinges and Carl Greenidge at Derby in 2007.
Tom Price was again in among the wickets (Michael Steele/Getty Images)
Taylor drove Luis Reece for six to bring up 300 and dispatched Brookes for another maximum on his way to a 60-ball 50.
Gohar drove Lakmal for six to reach his 50 from 65 balls and set the new ninth wicket record before he skied the Sri Lankan to mid-off.
The innings ended in the next over but Gloucestershire now had a big enough lead and enough overs left to put the home side under pressure.
Any chance of the game meandering quietly to a conclusion vanished when Derbyshire lost three wickets in the space of 17 balls with the arrears still in three figures.
Harry Came held his team together in the first innings but this time he lasted only five overs before he got an edge onto his pad and was caught at gully.
Price struck in the next over with a full-length ball that hit Haider Ali in front and alarm bells were ringing when Wayne Madsen went without scoring.
Derbyshire, pre-season promotion contenders, remain winless (Tony Marshall/Getty Images)
The veteran right-hander had his off stump knocked back by a ball from Price that straightened to leave Derbyshire in trouble.
Du Plooy decided to be positive from the outset, dancing down the pitch to drive Taylor for six over long off, but he was close to being run out just before tea which was taken with Derbyshire 64 behind with 40 overs remaining.
Brooke Guest stayed with his skipper for 13 overs before pulling Ajeet Singh Dale to midwicket the over after du Plooy was dropped on 33 by Miles Hammond at slip off Gohar.
Mitch Wagstaff, in his second first-class innings, shared a stand of 43 from 70 balls although Gohar thought he had him caught and bowled on seven only for the umpires to rule the ball had not quite carried.
Wagstaff faced 48 balls before he fell cutting Gohar but Derbyshire were now in front and Luis Reece joined du Plooy to finally close the door on Gloucestershire.
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