After two dismal draws at Watford and Wimbledon last week, the pressure was on as Hammers returned to the Boleyn for the first time since the horrific 4-3 defeat against West Brom three weeks ago, but Paul Jewell's men were sent back up the M1 with their tails between their legs as two goals either side of the break pushed Hammers up to seventh place.
An early strike from Kevin Horlock and an own goal by midfielder Jason Jarrett were followed by a brace from home debutant Marlon Harewood after the interval.
To make matters worse for the Latics, they were forced to play for most of the second half with nine men after first Matt Jackson and then Lee McCulloch were red-carded.
The day began brightly for Hammers when Deane broke clear on the right and fired in a powerful low cross that Horlock only had to make contact with in front of goal for his first strike since returning to the club back in August.
Chief tormentor Harewood then took over. Starting on the right of an attack-minded 4-3-3 formation, he beat three men on the flank in the 18th minute before cutting the ball back into the six-yard box where Jarrett attempted a sliding block but only succeeded in carrying the ball over the line with him on a greasy surface.
At the other end, David James wasn't even forced into a save, with wayward long-range efforts from Nathan Ellington and former Hammer Jimmy Bullard the best Wigan could muster following the early loss of striker Geoff Horsfield through injury.
Two minutes before the break, it was virtually game over when Latics captain Jackson was dismissed for a lunging, two-footed tackle on Hayden Mullins right in front of referee Stretton.
Hammers had chances to extend their lead immediately after the restart, as Harewood saw a shot blocked by goalkeeper John Filan and substitute Don Hutchison volleyed into the side-netting from 12 yards out.
Things then went from bad to worse for the visitors, as midfielder McCulloch, having already been booked for a nasty first-half tackle on Tomas Repka, was shown the red-card for another foul on the Czech defender.
Hammers took instant advantage, as Harewood wriggled inside the box and was felled by a stray leg. Referee Stretton ensured he definitely won't be receiving a Christmas card from the JJB stadium by pointing to the spot, and the Hammers striker picked himself up to coolly strike the ball past Filan.
The former Nottingham Forest striker doubled his tally and made it 14 for the season with 15 minutes remaining, when he raced on to a neat pass from Mullins and drew Filan before cheekily lifting the ball over the Wigan keeper and into the net.
The visitors battled bravely to restore some pride, with Bullard and Ellington trying their hardest to create some inspiration, but in the end it became a non-event as Hammers wore down the clock to leave their delighted boss looking forward to his first victory in charge and full of confidence as we prepare for the trip to West Bromwich Albion next Saturday - hoping to make amends for our recent encounter with the Baggies.