Luke McNally's winner against Derby was his third goal of the season
Bristol City's good run of winter home form continued as they beat Derby in the Championship to secure their fourth win in five games at Ashton Gate.
Centre-half Luke McNally's goal midway through the first half was the difference between the two sides as he struck the ball in from a Scott Twine free-kick.
Robins keeper Max O'Leary had earlier made two saves to deny Nathaniel Mendez-Laing and Marcus Harness, while Twine and Fally Mayulu missed chances to put Bristol City 2-0 up.
The win moves the hosts up to eighth in the table, three points away from the play-off places, while Derby - who remain with only one win away from home this season - drop a spot to 18th.
Bristol City head coach Liam Manning said before kick-off that his side had a score to settle after being swept aside 3-0 when the two sides met in the reverse fixture at Pride Park in August.
But it was Derby who started more on the front foot and almost found the net inside four minutes, as a deflected shot from captain Mendez-Laing forced Robins keeper O'Leary to make a diving save to his left to palm the ball away.
Former Robins winger Kane Wilson then whipped a cross into the box but Harness could not get his downward header on target and it bounced off the ground and went wide.
Bristol City had not posed any attacking threat until Twine stepped up for a free-kick on 19 minutes, and with trademark pinpoint accuracy launched the ball into the box for McNally to poke into the net to break the deadlock.
Twine almost made it 2-0 a few minutes later, when a lovely pass from Anis Mehmeti put him through one-on-one with keeper Jacob Widell Zetterstrom but Callum Elder raced back to make a last-minute block.
Chances continued at either end as Derby's Nat Phillips saw a header from a free-kick tipped over the bar by O'Leary and Ross McCrorie wasted a close-range effort.
Derby have suffered from their poor away form this season and despite boss Paul Warne making five changes to his side through the second half, the Rams created little in front of goal with Bristol City looking more likely to score again.
Mehmeti saw a shot denied while substitutes George Tanner and Mayulu then combined, but Tanner's pass to the Frenchman was a too far behind him to get his effort on target.
Two golden chances then went begging from Bristol City in the closing stages as Mayulu mis-kicked a volley from a handful of yards out and in a three-on-one Yu Hirakawa picked arguably the wrong pass to Mehmeti, whose shot was blocked.
'We've made this a tough place to come' - reaction
Bristol City head coach Liam Manning told BBC Radio Bristol:
"We've not necessarily always got the results here (Ashton Gate) but performance wise we've always been consistent, I think around some of the ones where we've not played great they always tend to be on the road.
"We said at the start of the season about making this a really tough place for teams to come and we've done that, three clean sheets in a row.
"Today was slightly different off the back of a fifth game in 14 games, today was around finding a way, digging in, showing resilience, coming together, pulling each other through it, because the lads are flat on their feet.
"I think today showed around the culture and what we've got in terms of a top group of professionals."
Britol City head coach Liam Manning speaks to BBC Radio Bristol following their win against Derby
Derby head coach Paul Warne told BBC Radio Derby:
"I didn't think we were anywhere near our best today, I thought it was a game that we could win and it just felt like a game too far for our lads.
"I just thought we had to get as much energy out of the group as we could, I don't think we played with much energy. There were moments where we got into the final third [in the] first half, second half was like we just tired out of the game.
"I just feel we need to regroup, freshen up, freshen the squad up a bit. We lost too many tackles, made some crazy decisions and definitely didn't do enough to deserve a win.
"To concede off a set-piece was really disappointing."
Paul Warne post-Bristol City (A)
