The side launched the new season with a draw with Derby County nine days ago and, speaking after today's game, Grayson thanked his charges for executing his gameplan.
"We always knew it was going to be a tough game because they have some very good players," he told the Sunderland website. "You have to give credit to our players for carrying out the instructions we've laid out in the last 48 hours.
"We knew they would have possession due to playing three at the back but we were happy for them to have it in certain areas, and ultimately we knew we would get opportunities on the counter-attack.
"We've always said that we have players who can hurt the opposition and you've seen that today with two great goals. Overall it was a pleasing afternoon."
Next up for Sunderland is a trip to Sheffield Wednesday on Tuesday night.