HernÃƒÂ¡ndez turned home NaniÃ¢â‚¬â„¢s cross after 17 minutes and slotted in his second 15 minutes from time before a simple Wayne Rooney tap-in and a straightforward shot from Fabio completed the rout late on.
Sir Alex Ferguson opted to rest 20-goal Dimitar Berbatov, preferring HernÃƒÂ¡ndez to partner Rooney in attack. And it proved a prosperous decision by the wily Scot as the Mexican forwardÃ¢â‚¬â„¢s double helped the league leaders overcome a spirited Wigan side.
Roberto MartÃƒÂnezÃ¢â‚¬â„¢s men made an encouraging start to the match. Victor Moses capitalised on sloppy play by Paul Scholes early on, but the 20-year-oldÃ¢â‚¬â„¢s effort was well-saved by the imposing Edwin van der Sar, who made several vital contributions in the United goal throughout the afternoon.
United took the lead against the run of play when Rooney and Nani combined well in midfield before the Portuguese winger crossed to an unmarked HernÃƒÂ¡ndez, who delicately steered the ball past Ali Al-Habsi.
James McCarthy had an opportunity to equalise moments later when he found himself through on goal, only to see his effort expertly saved by Van der Sar.
The next chance to rustle the Wigan net fell to Nani after Darren Fletcher won the ball in midfield and immediately found Rooney who in-turn fed the winger, but his shot flew off Al-HabsiÃ¢â‚¬â„¢s left post and harmlessly out of play.
The Portuguese international was in rampant mood and twice came close to cementing UnitedÃ¢â‚¬â„¢s lead after the break as the winger provided resistance to WiganÃ¢â‚¬â„¢s positive start to the second half.
WiganÃ¢â‚¬â„¢s best chance to draw level after the break came through Maynor Figueroa, who unleashed a ferocious drive which had to be beaten away by a fully-stretched Van der Sar.
But HernÃƒÂ¡ndez finally doubled UnitedÃ¢â‚¬â„¢s lead 15 minutes from time when he steered the ball past Al-Habsi after Rooney expertly fed the Mexico forward as he broke through the Wigan rearguard.
Rooney, who could have seen red in the first half following a cynical elbow on McCarthy, then tapped home substitute BerbatovÃ¢â‚¬â„¢s pass to cap a devastating break by the away side.
Substitute Fabio added gloss to the victory when he netted UnitedÃ¢â‚¬â„¢s fourth after abject defending by the Wigan defence.
Ferguson admitted Wigan had dominated the opening exchanges but heaped praise on HernÃƒÂ¡ndez for his composure in front of goal.
Ã¢â‚¬Å“First 20 minutes it was all Wigan, they had some great attempts,Ã¢â‚¬Â said the United boss. Ã¢â‚¬Å“HernÃƒÂ¡ndez is great in the penalty box, though, and second half I thought we were excellent.
Ã¢â‚¬Å“We’re very pleased with that performance today. We had to hang on a bit at times. Getting the first goal settled us down a bit.Ã¢â‚¬Â
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