Boss Richie Barker felt Crawley were denied a deserved point at Wolverhampton Wanderers by a "soft" penalty.
Billy Clarke had fired Reds level in injury time but Leigh Griffiths broke their hearts two minutes later when he fired home from the spot after Kyle McFadzean had blocked a cross from Kevin McDonald with his arm.
Barker said: "Losing like that is hard to take because I felt it was a soft penalty. Kyle wasn't looking to gain any advantage and it was his momentum that made the ball hit his arm.
"It's disappointing because I felt we were the better team for the majority of the second half and deserved a point."
Bjorn Sigurdarson had put Wolves ahead after just seven minutes but Crawley recovered well and would have been level at half-time if Joe Walsh had not missed from six yards.
They finally got their reward when Clarke fired home but in contrast to his manager the striker had no arguments with the penalty which gave Wolves their winner.
Clarke said: "We were the better team for 80 minutes so to lose in that manner right at the end is very disappointing.
"Nicky Adams watched it again on the television and apparently it was handball but we can still take a lot of positives from our performance.
"If we play like that every week then we'll be right up there come the end of the season."
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