Bolton passed another unwanted milestone as they slipped closer to relegation after a Mason Mount hat-trick gave play-off chasing Derby a 4-0 home victory.
It was Bolton's 26th defeat of a troubled Sky Bet Championship campaign, the worst record in the club's history, and only a string of saves from goalkeeper Remi Matthews kept the score down.
There was never any doubt about the result once Craig Bryson and Mount struck before the interval and the on-loan Chelsea midfielder scored twice in the second half as Frank Lampard's side moved to within two points of the top six.
Bolton's Championship status had been hanging by a thread and they were close to conceding in the sixth minute when a Mount effort from 25 yards deflected narrowly wide off David Wheater.
Bolton threatened in the 12th minute when Luca Connell burst into the box but he was crowded out and Harry Wilson broke dangerously, only for a heavy touch to let him down.
Although it was all Derby, Bolton had the first clear chance in the 22nd minute when Andrew Taylor crossed from the left and picked out Clayton Donaldson but his diving header went straight at Kelle Roos.
Four minutes later, Derby had their first opening when Martyn Waghorn's flick found Bryson but his shot from 12 yards was saved by Matthews who minutes later made another fine stop to deny Waghorn.
Derby were building pressure and Richard Keogh had a shot charged down before the breakthrough came in the 37th minute.
There looked a good case for a penalty when Wilson went down under Connell's challenge but the ball broke to Bryson who fired in from a tight angle.
It was now a question of whether Bolton could respond but the Rams scored again in first-half stoppage time when Mount rounded off a clever one-two with Waghorn to leave them in complete control.
The visitors scrapped but they offered little going forward and Derby were close to a third in the 48th minute when Wilson's 12-yard shot was deflected behind.
Mount sidefooted wide when he should have hit the target but he made no mistake in the 55th minute when he headed in from close range following a cross from Tom Lawrence.
It was about damage limitation for Bolton and Matthews prevented a fourth with a superb diving save to deny Waghorn, who then lobbed just over the bar.
Waghorn stabbed another chance wide before he was substituted but Mount completed a memorable afternoon by driving in his third from Ashley Cole's astute pass in the 82nd minute.
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