Fletcher scored in the 3-0 rout over the Magpies to seal Sunderland's first win of the season. A win, the Scotsman said, is made only sweeter by the fact that it comes against rivals Newcastle.
Newcastle defender Fabricio Coloccini was adjudged to have denied a goalscoring opportunity in the first half and was sent off.
Speaking after the game Fletcher reflected on the match and told the Daily Mail: "We needed the result, but it's obviously even better when it comes against your rivals."
"Newcastle put us on the back foot in the first 30 minutes, but when we got the penalty, the game changed."
The decision has been contested by Newcastle, but Fletcher believes that the referee took the right course of action.
"I was just looking at the ball, he added so I didn't know he was coming. When you're not expecting it, it's going to be a harder hit. He knocked me off. I think he just tried to stop me getting to the ball. It's a free-kick anywhere else, so why not a penalty?"