Two goals from Ross Stewart and a superb effort from Jack Clarke ensured Tony Mowbray began life in charge of Sunderland in the best possible fashion.
Having named an unchanged line-up from Saturday's 1-0 defeat to Norwich City, Mowbray's half-time comments inspired the Black Cats who emerged for the second period with a clinical edge and were, ultimately, good value for the victory.
Just 60 seconds after Danny Batth put a simple header off target, Sunderland converted their dominance into goals as Stewart smashed a left-footed shot under Viktor Johansson to send Wearside into raptures.
READ MORE: Jack Clarke masterclass, Ross Stewart brace: Sunderland 3-0 Rotherham player ratings
The floodgates then opened when Clarke, who was man of the match on the night, found Stewart with a smart pass to allow the Scottish international to finish easily past Johansson.
Clarke then scored the goal that his performance deserved. The 21-year-old cut in from the left, magnificently danced past three players and fired a right-footed shot into the bottom corner to put the game beyond doubt.
Here's how the Sunderland fanbase reacted to their team's third Championship win of the season, leaving them in eighth place.
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