Jason Knight's first goals in professional football were enough to give 10-man Derby a much-needed win over Charlton.
The hosts took an early lead when teenager Knight bundled home at the back post but soon found themselves reduced to 10 men when Krystian Bielik was sent off for a poor challenge on Conor Gallagher.
Knight looked to have made the points safe for the Rams, who went into the game on the back of seven matches without a victory, with a composed finish from Max Bird's cross.
The Addicks pulled one back from the penalty spot through Lyle Taylor, after Curtis Davies felled Gallagher in the area, and Derby were then indebted to a great double save by goalkeeper Ben Hamer from Ben Dempsey and Taylor.
Victory moved Phillip Cocu's men up to 17th in the table, two points and two places above Charlton.
It was a timely boost for the Rams, who will be able to call on the services of England's record goalscorer Wayne Rooney for the rest of the season.
Despite playing against 10 men for over 70 minutes the Addicks only really threatened in the final 10 minutes of the game, and have won just once in 13 matches to slip to seven points above the relegation zone.
Derby could give a debut to Rooney in Thursday's home game against strugglers Barnsley, while Charlton visit play-off hopefuls Swansea on the same night.
Derby boss Phillip Cocu: "I am extremely proud of how we performed. The discipline, how we defended and how we still played football with 10 men, we showed great character. The players stepped up today.
"Jason Knight had a fantastic game. Max Bird played like he's been in the team for five years. It's fantastic to see. Morgan Whittaker came on too and he made an impact.
"Rooney has so much quality and experience, so I am glad he is here. He is fit and would be ready to go, but needs a few games to build his minutes up."
Charlton boss Lee Bowyer told BBC Radio London: "We were poor from start to finish. We were out-battled and out-fought. We were second to all the second balls.
"We got what we deserved - nothing from the game. We weren't good enough. It's as simple as that.
"We got in to so many good areas but our quality with our final ball was very, very bad. We kept hitting the front man.
"Too many people were hiding. It wasn't good."