Sonny Carey's second-half goal earned Charlton a 1-0 victory over nine-man Sheffield United at the Valley.
Senegalese midfielder Djibril Soumare and captain Japhet Tanganga both saw red in the first half to leave Chris Wilder's side with a huge uphill battle.
The Blades had dominated the Sky Bet Championship match before their two dismissals.
It took the visitors just 20 seconds to win the first of seven corners in the opening 45 minutes.
Referee OIiver Langford ignored Patrick Bamford's appeals for a penalty after he went down under a challenge from Karoy Anderson on the left of the box.
Charlton goalkeeper Thomas Kaminski denied the in-form Bamford, who had scored six goals in his 11 appearances for United coming into the match in south-east London, at his near post.
Kaminski made an even better save in the 15th minute, sticking out his right leg to divert Tom Cannon's shot over the crossbar.
Tyler Binden's header dropped just wide of the left upright and Soumare hit the base of the right post shortly after the half-hour mark as the visitors bossed proceedings.
It looked a matter of time before the Blades made their superiority count, but Langford issued a straight red card to Soumare in the 35th minute after the midfielder produced an ugly, late, high tackle on Harvey Knibbs. Knibbs was carried off the pitch on a stretcher with what appeared to be an injury to his right ankle.
United's task became even tougher in the second minute of stoppage time as centre-back Tanganga was also sent off. The centre-back led with his elbow as he caught Carey in an aerial duel.
Charlton went ahead in the 46th minute with Carey volleying home first time from substitute Lyndon Dykes' knockdown. It was the midfielder's sixth goal of the campaign and ended a barren run of 12 games without netting.
Tyreece Campbell went close to a second in the 54th minute, but Blades goalkeeper Michael Cooper got down smartly to only concede a corner.
But the floodgates did not open for the Addicks, who found it hard to carve out openings and their patient approach play frustrated the home support.
Carey had a goalbound attempt blocked inside the box, with United substitute Gustavo Hamer blazing over at the other end.
Miles Leaburn had a chance to kill the match off in the closing stages, but Cooper pushed his strike out for a corner.
Andre Brooks cleared off his own goal-line to keep out Charlton skipper Lloyd Jones' header, which also took a touch off Blades substitute Tyrese Campbell.
Charlton's Nathan Jones:
"It doesn't feel like the euphoria you should have when you've beaten Sheffield United at home. A win is a win. It was a strange atmosphere. They started fantastically well and we needed our goalkeeper to keep us level.
"When they went down to 10 men, we had a little more control and then more control again at nine men.
"We made the right substitutions, we scored the goal and had other opportunities. You have to control the game. You can't just go gung-ho because they have good players - every time you turn the ball over they go at you.
"Two years ago this football club was losing to Northampton and were going 19 matches without winning. Now we are in the Championship, level on points with Sheffield United and above West Brom - ask any Charlton fan if they would have taken that.
"We could have been better today, but there was an edginess to everything we did. What Man City, Barcelona and Chelsea do against you is they work it and work it until the right opportunity comes along and then they score.
"I'm proud we have won the game. Could we have all made better choices? Absolutely. But we've just beaten Sheffield United for the second time this season."
Sheffield United's Chris Wilder:
"This is not an ill-disciplined club. There is a mistimed tackle and a mistimed header. Sam is having stitches on his ankle. The linesman is right in front of him and shrugged his shoulders.
"We should have had a penalty. It is brilliant centre-forward play by Patrick Bamford. He is in the box and about to pull the trigger.
"I've had some really big highs and really proud moments and I've got to say the way my team played today is right up there, in terms of the first-half performance and the adversity we were up against.
"Is it easier to play against nine men? Of course it is. But they fought every minute of the game for their football club. It is a completely different animal to when I took over.
"The disappointment, and this isn't through rose-tinted glasses, is that we should be out of sight at half-time, three or four. We never let the home team breathe - we got everything right. My only criticism of the afternoon is we need to be more clinical.
"The boy (Soumare) hasn't gone to top him. Everyone will slow it down. One hundred per cent we will appeal the second one. He couldn't wait to get his red card out."
