United only managed a 1-1 draw in Saturday’s Premier League clash at Old Trafford.
Javier Hernandez gave United the lead early in the second half while Newcastle striker Demba scored with a penalty.
Referee Mike Jones appeared to give a corner to Newcastle following a fair tackle by Rio Ferdinand on Hatem Ben Arfa, but he was persueded to award a spot-kick after talks with his assistant John Flynn.
“Everyone, including the referee, was astounded. He was put in a terrible position. Why can’t the referee overrule it when he is only eight yards away?” Ferguson told Sky Sports.
“The problem is that the referees are full-time and the linesmen are not, and whether he ever gets a game again, the assistant referee, is not for me to decide but it was an absolutely shocking decision.
“It costs you. Two years ago when the linesman gave the offside goal against Chelsea it cost us the league, so hopefully we’re not saying that at the end of May.”
“Listening to Alan Pardew’s interview and he said he thought they were the better team in the first half, I don’t know what game he was at,” added Ferguson.
“They made one chance in the match but in the first half Chicharito had four one-on-ones in the first half and on another day he takes two or three.
“In terms of creating chances we were fantastic, and if we play like that every week I’ll be delighted.”
