Teenager Jason Knight scored his first senior goals to give 10-man Derby a 2-1 win over Charlton at Pride Park.

With player-coach Wayne Rooney watching on ahead of his imminent debut for Derby, 18-year-old Knight pounced in each half to earn the Rams – who had Krystian Bielik sent off for a bad foul on Conor Gallagher in the 17th minute – a first victory since November.

An 83rd-minute penalty by Lyle Taylor gave the Addicks hope, but the home team hung on to move nine points clear of the Sky Bet Championship's bottom three.

The game was only 20 seconds old when Knight played in Martyn Waghorn but Dillon Phillips blocked his shot.

There was a good tempo about Derby and Charlton were punished in the 10th minute when Naby Sarr's loose pass allowed Andre Wisdom to cross and Waghorn's deflected shot was headed in by Knight.

Replays suggested Waghorn was offside but, with no VAR, the goal stood, although Derby's celebrations were short-lived as Bielik was dismissed for a lunge on Gallagher.

It was a wild challenge by the former Charlton loanee but, despite going down to 10 men, Derby remained on the front foot and the visitors did not threaten until the half-hour mark when Ben Hamer had to turn behind a Tom Lockyer cross.

Derby went close again when Jack Marriott's shot was deflected over and, although Charlton were getting into some good positions, their final ball lacked quality and Ben Purrington's dreadfully over-hit cross just before the break summed up their first half.

Hamer was forced into a diving save by Alfie Doughty at the start of the second period before Marriott had a great chance at the other end in the 50th minute when a ball over the top caught Charlton cold, but his lob was well wide.

Addicks midfielder Albie Morgan volleyed wide from the edge of the area when the ball dropped invitingly to him but the hosts went close on the break in the 57th minute when Marriott's low shot was saved by Phillips.

Gallagher had been booed constantly after Bielik's red card and there were loud cheers when he was booked for a foul as Charlton's frustration at failing to create so little against 10 men showed.

It was Derby who looked more likely to score again and they did so in the 77th minute when Max Bird's cross from the left fell to the unmarked Knight, who side-footed past Phillips from eight yards.

But Charlton were back in it six minutes later when Gallagher was tripped by Curtis Davies and Taylor sent Hamer the wrong way from the spot.

Suddenly the red shirts were swarming around the Derby box and Ben Dempsey thought he had equalised in the 89th minute, but Hamer made a great save low to his left and the Rams held on.