Simon Grayson’s Black Cats were promptly dismantled by Barnsley at Oakwell as Paul Heckingbottom’s side ran out 3-0 winners.
On-loan Chelsea man Ike Ugbo opened the scoring after half an hour with a fine strike into the bottom corner.
Harvey Barnes quickly followed up with Barnsley’s second before George Moncur wrapped up the scoring as his left-footed strike found the back of the net in the 67th minute.
The 4,200 travelling Sunderland fans were left dissatisfied with their team’s lacklustre display and will hope for much more next time out.
After bringing in a number of new recruits Harry Redknapp’s side still fell to defeat as Jaap Staam’s Royals took home all three points.