England are a team now - Rashford
Rashford found himself in Roy Hodgson's Euro 2016 squad mere months after his explosive emergence at United.
The dream turned into a nightmare as the then teenager – one of few players on the night to emerge with credit from his performance – came off the bench in the second half but was unable to avert a humiliating last-16 loss to Iceland.
There is an entirely different feel around the current England squad under Gareth Southgate, something Harry Kane's last-gasp heroics against Tunisia in Monday's Group G opener only fuelled further.
"The mood around the camp is a lot calmer from what I can remember of the last tournament but I think that's to be expected," Rashford said at England's Repino World Cup base.
"We were all fairly new to each other and we've managed to build relationships. The team really is a team now.
"That puts us in good stead for this tournament and future tournaments."
What a feeling! @FIFAWorldCup debut #ThreeLions pic.twitter.com/8fSMXYJsa7
— Marcus Rashford (@MarcusRashford) June 19, 2018
Despite the obvious feelgood factor engendered by beating Tunisia 2-1, Rashford insists an England team on form on the training field did not necessarily need the validation of Kane completing his brace.
"We already know that within ourselves. The games that everybody can watch, they are just an opportunity to showcase that and show everybody how far we've really come," he said.
"Even if we draw that game we stay calm and the next game is an opportunity to show what we've been working on and get the three points.
"That mentality has to stay because you're not going to win every single game. When you draw or lose you have to learn from it. As a team, we're capable of doing that.
"It doesn't matter about age or experience – if we have that togetherness we can all drag each other through."
Dele Alli underwent a precautionary scan after suffering a knock to the thigh in England's opener.
Rashford is hopeful the Tottenham midfielder will be ready to face Panama on Sunday, having come through his own struggles with a knee niggle during the final stages of the Three Lions' preparations.
"It's something that I've had before. The timing was annoying, for it to come just before we travelled. You have to stay calm in those situations," Rashford added, before explaining he will continue to take precautions against the problem for the remainder of the tournament.
"I knew what I had to do to recover fast enough for the [Tunisia] game. That will continue to happen throughout the tournament. I'll do recovery to stay in shape."