Wayne Rooney put United ahead from the penalty spot after referee Lee Mason sent off QPR defender Shaun Derry for a dubious foul on Ashley Young in the 14th minute.
Mark Hughes’ side prevented United from adding another until midway through the second half, when Paul Scholes’ hammered a low shot past QPR goalkeeper Paddy Kenny to secure three points.
“Ashley was a yard offside so I can understand Mark [Hughes] being angry and disappointed at that. You see these kinds of decisions every week though,” Ferguson told United’s website.
“The boy’s just got a little tug on Young, not a great deal but enough to get us the penalty. And unfortunately he was the last defender and had to be sent off.
“The sending-off didn’t help us at all. I was actually more confident before that in terms of the speed of our play and the movement of the team which was very good.
“The second goal from Scholes calmed everyone down. Before that we’d kept missing those vital chances. Welbeck was through, then we hit the bar and the post and balls were flying across the box, but it just wouldn’t go in.”
QPR remain in 17th place after Blackburn Rovers suffered a 3-0 defeat by West Bromich Albion on Saturday, and Hughes revealed the Loftus Road outfit will appeal against Derry’s red card.
“We’ll obviously try and appeal that and hopefully get that overturned by Wednesday,” Hughes said.
“We can ill-afford to have any more out. I think everbody understood that the boy was offside and that there was minimal contact. The boy has gone over too readily.”
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