Lee Johnson suffered a 1-0 defeat in his first match as Sunderland head coach as struggling Wigan ended a 10-match winless run.
Wigan striker Kyle Joseph struck in the 16th minute to put Sky Bet League One's bottom club in front at the Stadium of Light, and that was how it remained despite a second half when Sunderland pressed in search of an equaliser.
Johnson was appointed as their new head coach on a two-and-a-half year deal on Saturday, a day after Sunderland named Kristjaan Speakman their new sporting director, and was in the dugout for the match.
His first big call was to bring back Aiden McGeady, who made his first start since November 2019 after a fall-out with Parkinson.
The Irishman was quick to get involved and he went closest in the first half when he hit the side-netting after a brilliant through pass from midfielder Grant Leadbitter.
But Sunderland struggled to test goalkeeper Jamie Jones apart from that.
Joseph capitalised after Bailey Wright dawdled in possession in his own area before firing low inside goalkeeper Lee Burge's bottom-right corner.
After the restart, Jones was equal to a header from Josh Scowen and a drive from distance from McGeady, but those were as close as Sunderland got.