Wolverhampton:
O'Neill will officially take over as Steve Bruce's successor and watched on from the directors' box as Kieran Richardson put the Black Cats ahead early in the second half.
But after Sebastian Larsson saw his penalty saved by Wolves keeper Wayne Hennessey, Fletcher struck twice in nine minutes to secure the points for the hosts.
Wolves leapfrogged Sunderland, who are now just one point and one place above the relegation zone.
Topics mentioned in this article
Sunderland
Football
Mark Hughes
Alex Ferguson
Manchester City
Steven Fletcher
English Premier League
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