It was an embarrassing result and display for the Black Cats, who never looked like being anything but losers in a dire game of football.
Watched by a crowd of just 20,821, the encounter never really sparked into life in the first half.
Even the goals only provided a brief respite from a clash where the biggest highlight of the opening 45 minutes was referee Mike Riley's tumble in the middle of the pitch.
The Black Cats looked toothless up front, static in midfield and clueless at the back for much of the game.
To be fair the Latics weren't too much better in the early stages, but once they went in front the visitors never looked back.
The opening goal was a sad indictment of Sunderland's lacklustre defending on an afternoon when they simply weren't at the races.
Wigan won a free-kick out wide on Sunderland's left on 19 minutes. Josip Skoko floated the ball in and the Wearsiders defence stood statuesque as Paul Scharner fired under keeper Craig Gordon.
If that wasn't bad enough worse was to come from the hosts. Loan signing Jonny Evans looked to have any easy task as substitute Julius Agahowa chased down a long ball.
The centre-back should have put the ball in row Z, but turned inside and lost possession. His fellow defender Paul McShane beat Agahowa to the ball by a fraction, but could only succeed in toe-poking the ball into his own net.
Agahowa celebrated with his trademark somersault, but even the most generous of dubious goals panels will not be handing this effort to anyone other than McShane.
Sunderland, who had failed to compete all afternoon, were now at sixes and sevens and, while they tried to claw their way back into it, even their endeavour was second-rate on an afternoon that Keane will have nightmares about.
Young Irishman Ro'y O'Donovan went close with two late efforts, but even had he found the net it would have been of little if any consolation to Keane and his sorry Sunderland side.