Ben Youngs says there is more to come as England prepare for a World Cup semi-final against New Zealand.
The reigning world champions stand between England and a place in the final on November 2.
And while the All Blacks will present a formidable challenge in Yokohama next Saturday, England's quarter-final demolition of Australia underlined their own title credentials.
The 40-16 victory equalled England's record winning margin against the Wallabies, showcasing a ruthless approach as they scored 23 unanswered points after Australia moved to within touching distance.
"There is definitely more in us," England scrum-half Youngs said. "We feel we can still notch it up.
"Eddie (England head coach Eddie Jones) said to us afterwards 'it is the most exciting week to be a rugby player, so let's make sure we enjoy it, but let's make sure we get better'.
"That is the key – we have to keep improving.
"The exciting thing for me is I know there is more in this team. Against Australia, our edge D (defence) was a little bit vulnerable at times, a bit soft. We will tidy up some of those areas.
"What I am most pleased about is the fact that the game got tight and put us under pressure, and everything that we rehearsed and practised and sat in meetings about how we handle it and how we get a grip on it, we were able to do.
"That was really pleasing to do that in a huge game. Look back at South Africa in 2018, Scotland in the Six Nations, there have been times when we've been under the cosh and allowed cheap points.
"On Saturday, I thought that all that hard work we had done paid off."
As England move firmly into the tournament's business end, Youngs says that a summer spent together is reaping benefits.
"The World Cup is different because you get a huge period (of time) together and you are able to create bonds and invest more time into each other," he added.
"So that when it gets tough, you can trust your mates. We've got that club feel. That showed.
"That bit when they were really challenging our line and coming and coming in waves, and then they went to the scrum and kept coming. It was a tremendous defensive effort.
"Australia were always going to create opportunities. The pleasing thing was we stayed with how we wanted to play – no-one went off script.
"No-one tried to solve it on their own. We just stuck at it and eventually ground it down."
Youngs, meanwhile, paid tribute to dynamic England flankers Tom Curry and Sam Underhill, who dominated Australia's revered back-row double act of David Pocock and Michael Hooper.
"They have been phenomenal," he said. "What a fantastic day for those two to come out on top and test themselves against David and Hooper, who are tremendous players."