Matej Vydra's penalty earned Derby their first Sky Bet Championship win of the season as they triumphed 1-0 over Preston.
Vydra's 58th-minute spot-kick had too much power for Chris Maxwell to handle as Gary Rowett's men wrapped up a battling victory.
The Rams had turned up the pressure in the second half following what was an even first 45 minutes in which both sides had chances.
The victory could have been more emphatic for the home side, with Maxwell pulling off a number of good saves to keep the score down.
The visitors also had Darnell Fisher to thank for two goal-saving blocks right at the start of the second period.
Derby had started strongly with Andreas Weimann firing wide, despite having an empty net to aim at, after Maxwell fluffed an attempted clearance two minutes in.
Callum Robinson shot over following a swift Preston counter-attack and he was denied again seconds later when Scott Carson saved his long-range free-kick.
Weimann scuffed another effort wide from long range as the home side struggled to create clear chances.
Maxwell saved well with his feet on 19 minutes to deny David Nugent after Weimann's pass finally cut open Preston.
Robinson went into the referee's notebook on 36 minutes for a late challenge on Johnny Russell as the tackles began to fly in.
Maxwell collected a loose ball as Nugent threatened to pounce after Bradley Johnson's low shot came through a crowd of players on 39 minutes.
Nugent also went into the book on the stroke of half-time for fouling Maxwell.
A brilliant block on the line by Fisher denied Nugent a certain goal right at the start of the second half.
It came at the end of a superb break by the Rams, which saw Vydra burst past three defenders to create the chance.
Maxwell beat Vydra's goalbound header away moments later as the hosts cranked up the pressure.
Fisher's lunging block was enough to keep out a powerful effort by Weimann on 56 minutes.
But Derby were awarded a penalty after Greg Cunningham tugged back Curtis Davies from the resulting corner.
And, although Maxwell got his fingertips to Vydra's shot, he was unable to keep out the perfectly-placed penalty.
Russell was inches away from making it 2-0 five minutes later when he let rip with a 30-yard strike.
And Russell threatened again on 73 minutes when he failed to get enough power and bend on a curling effort.
Paul Gallagher curled a tame free-kick into the hands of Carson on 80 minutes, before Alan Browne had a volley saved in the first minute of added time.