Charlton dropped two places in League 1 after a controversial stoppage-time equaliser from MK Dons at The Valley.

A penalty, given by the assistant referee, who seemed further away from the challenge than the referee, handed MK Dons the chance to level which they duly converted.

It was the second time the visitors came from behind as Charlton looked to have won the points with an own goal in the 87th minute.

Charlton got off to the best possible start when Magennis headed them ahead.

He may have suffered World Cup qualifying heartache with Northern Ireland during the international break but Magennis quickly put that behind him.

A sweeping Charlton move saw Jake Forster-Caskey win a corner and it was his delivery that Magennis nodded in from close range with visiting keeper Lee Nicholls flapping.

At times, MK Dons were chasing shadows as the interplay and quick passing by Charlton's forward carved them apart.

But for all their possession and early dominance, the Addicks were only able to register long-range shots from Ahmed Kashi and Ricky Holmes for their efforts.

Encouraged by the home fans, centre-back Naby Sarr strode forward and saw his 25-yard left-foot drive comfortably saved by Nicholls.

The Addicks were denied a second by the woodwork on 24 minutes when Forster-Caskey's deflected effort hit the inside of the post and went across the face of goal.

Sarr failed to convert a Holmes free-kick while MK Don's only effort of the first half saw Peter Pawlett's shot deflected behind for a corner.

The action livened up just before the break with a couple of niggly fouls, Magennis was booked for barging into Ed Upson while George Williams fouled and then tangled with Holmes to spark a melee, earning him a yellow card from referee Andy Woolmer.

Charlton started the second half in positive fashion and nearly added a second on 49 minutes. Magennis played in Mark Marshall but, having got clear of the last defender, his low shot was blocked by Nicholls.

MK Dons used all three substitutes in the space of four second-half minutes and it paid immediate dividends with a 63rd-minute equaliser.

Scott Golbourne's delightful cross from the left-wing was met at the far post by substitute Kieran Agard, who expertly diverted his header beyond Amos.

The visitors should have turned the game on its head just three minutes later but Chuks Aneke wastefully blasted his shot high and wide of the target after being sent clean through.

Charlton had a glorious chance to regain the lead eight minutes from time when a deep cross was met by the unmarked Sarr but he could only direct a weak left-foot effort straight at the keeper.

The Addicks then appeared to have won it with three minutes left when Golbourne turned the ball into his own net at the far post.

But MK Dons levelled it in stoppage time. Referee Woolmer first said no when Pawlett went down in the box but his assistant flagged for a penalty and Agard stepped up to level from the spot.

Charlton: Amos, Kashi, Marshall (Ahearne-Grant 87mins), Magennis, Holmes, Reeves (Fosu 66mins), Konsa, Forster-Caskey, Solly, Dasilva, Sarr. Subs not used: Phillips, Jackson, Aribo, Dodoo, Dijksteel.

MK Dons: Nicholls, Williams, Wootton, Upson (McGrandles 62mins), Ariyibi (Nesbitt 62mins), Aneke, Pawlett, Golbourne, Seager (Agard 58mins), Ebanks-Landell, Gilbey. Subs not used: Sietsma, Walsh, Brittain, Thomas-Asante.

Attendance: 10,577 (602 away).