Steve Borthwick’s side got their tournament off to an excellent start in Marseille, recovering from the early dismissal of Tom Curry to secure a vital 27-10 victory.
While a commanding display with the boot from George Ford, who kicked six penalties and three drop goals, led the way for England, the win was also built on a fine 14-man defensive performance that suffocated the Pumas.
It took Argentina 75 minutes to add to Emiliano Boffelli’s fifth-minute penalty despite their numerical advantage, with Pedro Rubiolo crashing over in the final moments with England’s win already secure.
A spirited and, Curry’s challenge aside, largely error-free performance was a far cry from the final warm-up fixture against Fiji, where England dropped off nearly 30 tackles and struggled to slow the Pacific Islanders’ ball.
And Steward has revealed a few stern words from Sinfield (appointed defence coach and Borthwick’s key lieutenant last December) after that showing also helped bring about a significant improvement.
“We got a bit of a rocket after that game,” conceded Steward, who previously worked with the rugby league legend at Leicester. “There were no complaints about that, it needed to happen.
“We had a very thorough review, which we needed, and I think we reaped the benefits out there [against Argentina]. That was necessary for that to happen.
“Kev [Sinfield] is big on covering each other’s backs. That’s his big thing. He wants a defensive unit that are going to work incredibly hard for each other and, when it goes wrong, cover up for each other.
“That’s what makes Kev such a good defence coach, he’s so inspiring. He motivates us so much and he’s the sort of bloke you don’t want to let down. That’s testament to him as a bloke. When you go out there, part of it is you do it for him. You don’t want to see a guy like that who puts his heart and soul into us in his work with his defence feel let down.”
Steward had only a single tackle to make in Marseille, with England’s frontline defenders preventing a dangerous Argentina side finding any sort of rhythm.
The Pumas had been expected to be England’s toughest test in Pool D, but lacked accuracy and direction to exploit their opponents.
Sinfield said he was pleased to see his side develop defensively, though admitted to a degree of frustration over the late concession of Rubiolo’s score.
“I am pleased but I’m also really disappointed with that final passage,” the England defence coach said. “I’d have loved to keep them to zero tries. To do that against a world-class team like Argentina would have sent a message out.
“The big message was we have to be better. The boys have been excellent. I’ve really enjoyed working with them, but we’d not seen the transfer. Thankfully we started to see some of that on Saturday.
“We saw lots of what we had seen in training, which is pleasing but I still feel there is so much in this team, so much improvement, so much growth. To get the win, given the noise that has been around us, the way the group have really circled the wagons – metaphorically that is – is really pleasing. We saw a fight, a spirit and attitude that the people at home supporting us and in the ground last night would have loved to have seen.”
England next take on Japan in Nice on Sunday 17 September. Jamie Joseph’s side, quarter-finalists four years ago, opened their tournament with a bonus-point win over Chile.
“They are a big ball movement team,” Sinfield said of the threat posed by Japan. “We know they will bring some different challenges with how they move the ball. They have got some big men. They have got some power. They have got some pace, but they are a very skilful team. It will be another challenge for us.”