Graeme Jones felt that a “huge decision” went against his Luton side as they fell 3-1 to Charlton at the Valley.
A second-half effort from James Collins was ruled offside, with the Sky Bet Championship strugglers still level in the game.
After going behind 10 minutes after the disallowed effort – and conceding a third late on – Luton are at the foot of the table, still four points off safety.
However, Jones believed ruling the Collins goal out was an error, and that it would have changed the game had it stood.
He said: “I’ve got no complaints with the lads, the big moment in the game was our offside goal, which we’ve looked at and it wasn’t.
“They’re huge decisions and they were given against little Luton again, which I don’t like because at 2-1 up you’re in the ascendancy.
“We give a silly penalty away and we’re chasing the game.
“I’ve got no complaints from the players in terms of effort, having the temperament to play. But if there was ever something that swung on a big decision that was it.
“We were in a really good moment – if we had gone 2-1 up we understand how to control football matches, and I would have been very confident.”
Charlton had the first real opportunity in the 14th minute, when Naby Sarr turned and shot in the area – but saw his effort rifle off the crossbar.
The best chances still fell to the hosts, and on 27 minutes Alfie Doughty shot just inside the area, which forced keeper Simon Sluga to tip over.
Lyle Taylor broke the deadlock in the 34th minute, when he was able to turn and shoot past the outstretched arms of Sluga for his 10th goal of the season.
The lead – and the joy of the Charlton fans – was short-lived, however. Two minutes after Taylor opened, Luton equalised when the home defence failed to clear the ball properly, allowing Harry Cornick to fire home.
Collins had the ball in the back of the net in the 51st minute after he put the final touch on a shot by Cornick, but he was adjudged to be offside.
With Luton denied, they contributed to their own downfall 10 minutes later, when Collins handled a shot by George Lapslie, Taylor converting the following penalty.
Lapslie, the 22-year old midfielder, netted his first league goal for Charlton three minutes from time, converting from close range after playing a one-two with Macauley Bonne.
Victory puts the south London side five points above the drop zone, and manager Lee Bowyer believed his side deserved their victory.
He said: “I thought we created enough chances in the second half to win the game comfortably.
“We moved the ball quicker, our movement off the ball was better. I thought we deserved to win the game.
“Lyle’s first goal was very good, I see him do that every day in training, that’s what he’s capable of doing. He scores from nothing.
“I’m pleased for George, he’s been out a long while with a hamstring – it’s good to see him out there.
“It was a big three points, they all are now.
“Every point is valuable – nothing is given to you in this league, you have to earn it. Today we earned the three points.
“There’s a lot to play for, there’s a lot more teams in this scrap than I think people realise – it’s the teams above us that are going to get drawn into this.”
‘The pure simplicity of the way Slot has managed the squad is probably the biggest thing I could say about him. It’s not broken, so let’s get on with it’: Liverpool legend full of admiration for Jurgen Klopp's successor at Anfield
‘I trained at Spurs and thought they’d give me a chance. But I received a letter thanking me but saying they didn’t think I was good enough – I was gutted’: How Tottenham missed out on signing Wales legend John Toshack
