This was a good night for the Aston Villa manager and an interesting one too for Fabio Capello with James Milner and Ashley Young reminding the England manager that there are plenty of good right-footed midfielders to call on in the absense of the stricken David Beckham.
Milner, in particular, capped a towering performance with the winner that leaves Villa breathing down the necks of top-four rivals Liverpool and Manchester City, and within three points of Tottenham with a game in hand.
He's a winner: James Milner celebrates his strike at the DW Stadium
His 10th goal of the season also gave O'Neill his first Premier League win as Villa boss in March after nearly four years in the job, pushed Villa closer to Europe and enhanced his World Cup hopes.
O'Neill said: 'James is not only ready for the Champions League, if things go all right and he stays clear of injury there's no reason he can't participate for England.
'He gave an extroardinary performance. Since stepping into centre midfield his game has come on tenfold. We've been crying out for a midfield player scoring double figures.
'It was important for us to close the gap on the others. It was brilliant win. I saw Wigan beat Liverpool last week and that's what we were up against.'
Villa just about deserved their win. But a second defeat in four days was scant reward for a Wigan side who at times threatened to do the same to Villa as they did to Liverpool on this ground little more than a week ago. The same, O'Neill had not forgotten, as they did to his side on the opening day of the season.
On target: Wigan's Gary Caldwell scores past the diving Brad Friedel
Wigan certainly started the better of the two sides even though Young had the ball in the net twice in the opening quarter of an hour.
The first effort, a casual lob over Chris Kirkland, was executed long after Steve Bennett had blown for offside but the second, turning in Agbonlahor's low cross, was a tighter call for the referee and his assistants.
There was no question of offside when Villa broke through in the 25th minute, however, because it was a Wigan player who scored it for them after the home side had failed to clear the danger from a series of corners.
Stewart Downing sent in another cross from the right, John Carew headed back across goal and James McCarthy seemed to be in two minds as he turned the ball into his own net from five yards.
Calamity: James McCarthy scores an own goal past Chris Kirkland
There were several moments of stunned silence in the DW Stadium before the Villa fans at the other end of the ground realised what had happened and launched into celebration.
It only lasted for two minutes, however, as Villa conceded a freekick 30 yards out. Charles N'Zogbia's inswinging cross picked out Gary Caldwell and the Scot, who had such a torrid time in Saturday's damaging defeat at Bolton, went some way towards making amends with an emphatic header past Brad Friedel.
At that stage a genuinely entertaining game could have gone either way. Wigan fans thought Marcelo Moreno had put them in front with two minutes of the restart as his ambitious effort from range curled into the side-netting and Caldwell cleared from under his own bar after James Collins' header had beaten Kirkland.
But there was to be no reprieve for the Wigan keeper from a corner moments later. First he flapped at the ball and then saw it only half cleared to the edge of the box. There was Milner to rifle it back through a crowd of players and past the stranded keeper.
It was a sickening blow for Wigan boss Roberto Martinez whose flying start to life as a Premier League manager at Villa back in August must seem like a long time ago.
'It was a very open and exciting game but we lost because of the nature of the goals we conceded,' said Martinez. 'Every point has an extra significance now and we all need to pull together. The game against Burnley here on Saturday is vital and we will be ready.'
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