Charlton Athletic 2 (Kashi 63, Magennis 78), Oxford United 3 (Henry 76, Kane 89, Ledson 90+4)

The U’s trailed 2-1 heading into the 89th minute, but Todd Kane equalised with a smart finish, which was then improved on by Ledson’s precise 20-yard effort at the death.

The visitors were facing an uphill battle after losing Wes Thomas in the warm-up and then Jon Obika in the first half which left them without a recognised centre forward.

The incline grew steeper when an error by John Mousinho saw Ahmed Kashi open the scoring, but substitute James Henry equalised.

United though appeared to have thrown it away when Josh Magennis struck within two minutes to put the hosts in front again.

But there was no doubting the visitors’ character, who came up with a late surge which rewarded their 1,381 fans who made the journey to the Valley in what was an incredible turnaround.

• Oxford United players and substitutes celebrate Ryan Ledson's late winner

Derek Fazackerley made a statement with his selection, as Dwight Tiendalli, Agon Mehmeti and Gino van Kessel were left out of the squad.

Full backs Kane and Ashley Smith-Brown were handed debuts, while Joe Rothwell and Alex Mowatt returned from injury.

But the caretaker boss was forced to promote Obika from the bench after Wes Thomas picked up a problem in the warm-up.

United held on to Simon Eastwood amid approaches from Barnsley late in the transfer window – and that decision looked even better in the eighth minute, when the goalkeeper parried a stinging shot from Tariqe Fosu.

The lively winger, scorer in October’s reverse fixture, then laid on a chance with a cross which Mark Marshall headed tamely wide.

The game was being played at a high tempo and United’s noisy away contingent almost had a goal to celebrate in the 16th minute.

Obika collected a high ball forward and from 20 yards out his right-footed snap-shot beat goalkeeper Ben Amos but smacked into the angle of post and crossbar.

It was as close as United came before the break, but at the other end they worked hard to look more solid defensively than in recent weeks.

Aaron Martin made a couple of important blocks, while on the half-hour mark fellow centre half John Mousinho’s diving header snuffed out the danger from Josh Magennis’s knock-down.

United broke quickly, but Josh Ruffels’s effort flew wide from 25 yards.

Fazackerley was then given a selection headache when Obika went down with an injury.

With Thomas already ruled out, plus Mehmeti and Van Kessel left at home, there was no chance of a like-for-like replacement.

Instead, Malachi Napa was thrown on to lead the line as an unorthodox centre forward.

It was hardly ideal, but United got through to the interval with the game goalless.

Eastwood was called into action early in the second half, parrying a powerful low shot from Magennis.

But United were still well in the game and showed signs they could make the makeshift system work.

Rothwell was their driving force and just after the hour he embarked on a terrific run as Charlton’s defenders backed off. He slipped in a pass for Napa, whose first-time shot was well parried by Amos.

But just as the afternoon was looking up, United shot themselves in the foot.

A ball over the top put Mousinho in two minds, but although he appeared to have dealt with the danger, the U’s skipper failed to clear.

Magennis latched on to the ball, which reached Kashi, who slammed a shot into the net from 15 yards.

It was a desperately soft goal to concede, undermining an hour of hard graft.

United wobbled briefly, before drawing level 14 minutes from time.

The visitors had been crying out for someone to take responsibility in the final third and Henry took matters into his own hands, picking out the far corner of Amos’s net from 18 yards.

It sparked wild scenes in the away end, but United were level for just over a minute.

Jay Dasilva got round the back and from his low cross Magennis could not miss from close range.

United had to come from behind again, but their luck was out seven minutes from time when Kane’s lovely low cross was swept on to the outside the far post by Isaac Buckley-Ricketts.

But they kept going and the away end exploded again in the 89th minute.

• Todd Kane (No 19) made it 2-2 in the 89th minute

Substitute Ricardinho and then Ruffels did well down the left and when the low cross came in, Kane came up with an accomplished finish to equalise.

United looked the more likely side to snatch a winner in the five minutes of stoppage-time – and they got it with Ledson’s stunning finish.

Charlton Ath (4-2-3-1): Amos, Solly, Konsa, Lennon, Dasilva, Kashi, Forster-Caskey, Marshall (Zyro 69), Mavididi (Kaikai 69), Fosu (Aribo 87), Magennis.

Unused subs: Phillips, Jackson, Bauer, Reeves.

Booked: Lennon.

Oxford Utd (4-2-3-1): Eastwood, Kane, Martin, Mousinho, Smith-Brown, Ledson, Ruffels, Rothwell (Ricardinho 78), Mowatt (Henry 70), Buckley-Ricketts, Obika (Napa 34).

Unused subs: Shearer, Dickie, Carroll.

Booked: Ledson.

Referee: Keith Stroud (Hampshire).

Attendance: 11,747 (1,381 visitors).