Wigan midfielder Shaun Maloney scored the winner in the 50th minute after the Scotland international collected the ball from a short corner and curled his finish past United goalkeeper David De Gea.
The Red Devils posed little attacking threat but Phil Jones had a strong claim for a penalty rejected by referee Phil Dowd in the second half after his cross was handled by Maynor Figueroa in the Wigan area.
“It was a disappointing performance throughout the game,” Ferguson told United’s website. “We didn’t reach the levels that we have in the last few months so I think we got what we deserved.
“Wigan are a good team and they are very underrated. The position they’re in is false – they have been playing some of the best football in the league.
“They play with three centre-backs which gives them time on the ball and it was very difficult to stop their early possession.
“We decided to put three midfielders up against them in the second half and I think we were better to a degree, but we didn’t deserve to win the game so I have no complaints.”
Victor Moses thought he had netted the opener just before the half-hour mark when he powered a header past De Gea – but Wigan defender Gary Caldwell was dubiously penalised for impeding United’s Spanish keeper.
Jones contested Dowd’s decision to award Wigan a corner which subsequently led to Maloney’s goal, with the Red Devils defender adamant the ball had deflected out of play off Wigan’s Jean Beausejour.
The 20-year-old defender was aggrieved again when his cross was handled by Figueroa in the Wigan penalty area, but Ferguson admitted after a soft decision for United’s first goal in their 2-0 victory over Queens Park Rangers on Sunday, their luck had finally run out.
“He [De Gea] was pushed in the net, that was obvious and the linesman saw that one,” added Ferguson,
“He [the same linesman] didn’t see the clear penalty kick in the second half however. It was a clear handball, but as I say, sometimes you get the decisions and sometimes you don’t.
“We got a break on Sunday with the first goal but tonight we didn’t get one. It evens itself out over a season and my experience of these things says it happens, so you just have to expect it.”
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