Oliver Rathbone's seventh goal of the season earned play-off chasing Wrexham a 1-0 victory at Charlton in the Championship.
The Red Dragons withstood heavy pressure in the closing stages as they extended their winning run to three matches.
Charlton were forced into a goalkeeping change before the match with Thomas Kaminski, an ever-present in the league this season, missing out with a hamstring injury and replaced by Will Mannion.
The hosts also lost right-sided centre-back Reece Burke 11 minutes into the match with Kenyan international Collins Sichenje, signed in the winter transfer window from Serbian side Vojvodina, coming on for his home debut.
Charlton made a strong start in SE7 and were left to rue their failure to convert a couple of major opportunities.
Tyreece Campbell's pass found Luke Berry in space in the Wrexham penalty area but the attacking midfielder's decision to work more of a shooting chance saw his attempt blocked by Issa Kabore.
There was arguably an even better opportunity for the Addicks to go ahead in the 28th minute.
Sonny Carey's shot was deflected into the path of Harry Clarke, six yards out, but the Ipswich loanee could only steer his attempt past the left upright.
Wrexham punished the hosts on the half-hour mark as Rathbone, who signed a contract extension earlier in the week until the summer of 2028, showed ingenuity to slot them ahead.
Nathan Broadhead's cross was headed clear by Charlton captain Lloyd Jones but Rathbone produced a smart low threaded finish into the bottom right corner of the net from just outside the penalty area.
The south-east Londoners have not scored a first-half goal at home since November 22, a run of nine league matches.
Four minutes after the interval it needed Addicks defender Kayne Ramsay to make a perfectly timed block to deny Lewis O'Brien from Kieffer Moore's pass
Charlton struggled to fashion openings in the early stages of the second period until Campbell headed over a cross by Lyndon Dykes in the 68th minute.
Referee Farai Hallam ignored appeals for an Addicks penalty after Clarke went over inside the box while Mannion held on to substitute Josh Windass' shot.
Charlton kept pushing Wrexham back as they chased a leveller and Miles Leaburn volleyed over a Carey cross at Arthur Okonkwo's near post while Sichenje smashed over from a corner.
Wrexham goalkeeper Okonkwo made a superb save down to his right to turn Carey's full-blooded attempt out for a corner just before the contest ticked over into additional time.
Charlton's Nathan Jones:
"The level of performance was outstanding but how we haven't scored three or four, I don't know.
"It was a dominant performance - we were excellent in how we moved the ball. We limited them to just counter-attacks but good sides find a way to win games. They are clinical.
"They weren't just half-chances - they were clear cut.
"Bezza's chance is unbelievable, I expect him to score that, because that is the player he is.
"Harry Clarke's chance is gilt-edged. Their keeper makes an unbelievable save at the end. The stats said we only had 12 shots - I couldn't believe that.
"We scored more in midweek from three shots. Today, if we had been a tenth as clinical we would have won the game. That is the frustrating thing.
"You can say they defended the box well, but they haven't. We have missed chances today.
"I want to be in here eulogising about a fantastic performance but I'm not - I'm kicking myself because we lost the game."
Wrexham's Phil Parkinson:
"We showed incredible resilience today to get the win.
"There were some key moments in the game. Brilliant blocks by (Issa) Kabore and (George) Dobson - then a brilliant finish from Ollie.
"Arthur made a save from their first shot on target - but what a save it was. We know Carey is lethal from those situations. He has hit it low and hard, through legs, and Arthur has produced a match-winning save.
"The way we defended the box today was exceptional. We knew, coming here, that it would be about first contacts from set-plays and general play.
"Think of how many times the ball came into the box today and it came back out with a Wrexham head on it or reacting to the second ball.
"Broady (Nathan Broadhead) did well to skip past the lad marking him and Rathbone has done what he has done so many times for us. He is so calm in those situations. It is a really good finish.
"We had some gilt-edged chances in the second half and when you don't take them it creates a bit of pressure. But we saw it through well today. When you put players of the presence of Dan Scarr and Zak Vyner on then it helped the rest of the team."
