The French midfielder scored the winner from the penalty spot after Brian Brobbey was fouled, taking his tally to four goals across all competitions this season.
Speaking after the match, he said the performance reminded him of the Black Cats’ displays last season, while praising his teammates' fighting spirit and the strong support from the home fans throughout the encounter.
"Like I said before the game, it was really important for us to get back to our principles. I think the way we fight, we were together,” he told the media.
“Not only the players, the fans. It was amazing. The game looked more like last year, we can see this afternoon that we are a family, and this is the most important thing.
"I think after Leeds and Brentford games, we felt that we were in a good way, but after that we had two tough games.
“It wasn't the best game we've had in terms of football, but we came back to our principles. This is the most important thing. We've got a few days where we can rest, then we have to go again.
"We have to be together, and I think today was the case. Of course, it's not easy, but the season is long. We still need around another 32 points to be safe, we have to fight. We know the league is relentless, we try our best.
"To take three points against Chelsea at home ahead of the international break, for the confidence it is top."