Town boss Graeme Jones was left feeling hugely disappointed to have another tight offside call go against his side during Saturday's 1-1 draw with Stoke City.
On 70 minutes, the Hatters thought they have levelled the scores, when George Moncur's long range shot was parried by Jack Butland, only for Harry Cornick to crash in the rebound.
However, the linesman's flag was raised to chalk the goal off, similar to a week earlier at Charlton, as that time Cornick was provider, his cross-shot was turned in by James Collins, only for that strike to also be adjudged offside.
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Speaking afterwards, Jones said: "They’re telling it was a really close call and obviously if it’s a close call, it goes against Luton, we should all know that by now.
"If that’s as close as I think it is, that’s two in seven days.
"I’ll look at it, I don’t want to say too much, but if it’s margins again and it goes against you, it’s incredibly disappointing."
Striker Collins admitted he didn't have the best view of the goal, saying: “I know the one at Charlton was definitely onside, so we got done a little bit there, but I don't know about Harry's today.
"He thought it was close, but whether it was offside or not I'm not sure."
Town's leading scorer, who did rescue a point in stoppage with his 11th of the season from the penalty spot, was still annoyed his effort at the Valley had been ruled out seven days earlier.
He added: "It was as a massive turning point in the game as that would have put us 2-1 up.
"We're away from home then and we could have done what Stoke did to us today.
"But it wasn't to be and we lost the game, which is obviously very frustrating."