Dutch midfielder Kenzo Goudmijn joined Derby from Eredivisie side AZ Alkmaar in July
Derby County made it eight successive home league wins as they eased past previously unbeaten Bristol City with a clinical display at Pride Park.
The Rams were on the back foot for much of the first half and had limited possession, but still looked threatening in attack.
And, after City’s Sinclair Armstrong and Scott Twine both went close, Dutch midfielder Kenzo Goudmijn's fine strike from the edge of the box put the hosts 1-0 up.
With City increasingly on top, Jerry Yates teed up Kayden Jackson to fire in his third goal in five games this season after the break.
A first senior goal for David Ozoh, a calm close range-strike, wrapped up victory in the final minute.
Derby’s third home win out of three this season was as much down to their tactical nous as their ruthless attacking.
Boss Paul Warne has said his side are not “Championship ready”, but while they may struggle to compete in terms of finances and experience, their energy and organisation once again stood out.
City were on top early on and had the better chances, notably Armstrong, who was twice denied by Swedish keeper Jacob Widell Zetterstrom.
But Derby, who had looked dangerous on the break, always seemed likely winners after Goudmijn’s cool, low strike deflected in for his first goal, on his sixth appearance, for the club.
A brilliant Curtis Nelson block kept out Twine’s shot and ensured Derby led at the break.
Jackson’s powerful right-footed effort beat keeper Max O’Leary from 15 yards to make it 2-0
Nathaniel Mendez-Laing and Yates both hit the post as Derby chased a third goal , which arrived when Ozoh crashed the ball home on the rebound following O’Leary's initial save from an Ebou Adams shot.
Derby boss Paul Warne told BBC Radio Derby:
"I think this was the favourite of my career here. We looked like a team I want.
"The first 10 minutes they were much more competent on the ball than we were and made it difficult, but second half we were much better.
"Our performance was right up there. I loved it - and even if we'd have come off and they'd have nicked two in the last minute, I'd have still loved it.
"I thought we were really good. I'm really pleased with a lot of performances. It was the proudest performance I have witnessed."
Bristol City boss Liam Manning:
"It just wasn't good enough. We started OK and arguably could have been ahead before Derby scored.
"Performance-wise, in the first half there were some good things, positive things.
"We could have been a bit braver with the ball but then the second half just wasn’t good enough. It wasn't us and that was probably the most frustrating thing.
"We’ve spoken before about going behind and staying true to how we play and focusing on what we do rather than chasing the result and it felt in the second half we just disconnected and made some crazy decisions."
