All eyes were on Aaron Rodgers and his Green Bay side as the Packers became the final NFL team to travel across the Atlantic for a regular season game, with green and gold shirts seen across a sold-out Tottenham Hotspur Stadium.
Green Bay started on the front foot but it did not prove a victorious first trip to London, where the Giants dug deep to overcome a 10-point half-time deficit to triumph 27-22.
Barkley scored what proved to be the game-winning touchdown after returning from a shoulder injury that threatened to end his day as New York moved to 4-1, meaning they have already matched last season's win total.
"If anyone want to take us serious or not, the main thing we got to focus on is interior, inside our building, continue to love the process and continue to get better and continue to lean on each other and find ways to get wins," the electrifying running back said.
"It's a great start. 4-1. It's where you want to be. But you can't get too caught up in it.
"You've just got to keep working and there's a reason why we're 4-1 and that's because of the process.
"That's because we've got guys coming in and working and believing in the system, setting the culture, setting the standard and following it. That's what it means.
"We've got to continue to do that and if we continue to do that, continue to believe in each other - when we look back at this thing we'll be pretty excited."
Barkley does not think Sunday's win is a statement to the league and downplayed the injury that saw him temporarily return to the locker room, saying he "just got banged up" and only wanted to get back in to help the team.
That competitive spirit underlined the togetherness and drive being cultivated by Brian Daboll, who has impressed since becoming Giants head coach in the summer
Asked why things have turned around this season, Barkley said: "Obviously just a standard, the culture, the coaches.
"But to be completely honest what I believe has changed is we are finding ways to win games.
"There's been a lot of times throughout my career that we've been in a situation in the past and we always end up on the wrong side of it, and we are finding a way to end up on the right side of it. That's just all because of the process.
"All because of the way that we come to work. All because of the way that we have got guys that love to be coached the way our coaches coach.
"Everybody from all the way up to the top of the building to training staff to being in lunchroom, equipment guys, everybody. We got a really good thing going in the facility and we've just got to keep building on it."