Head coach Eddie Jones says England will improve after his side started their World Cup campaign with a laboured 35-3 victory against Tonga.
England took 76 minutes to secure a four-try bonus-point victory against opponents who conceded 14 tries against New Zealand two weeks before.
"The World Cup is not a 100m sprint. You don't have to come out of the blocks and be fantastic," said Jones.
"What you have to do is improve and have the mindset of improvement."
Two tries from Manu Tuilagi and one each from Jamie George and Luke Cowan-Dickie secured the victory but handling errors meant other try-scoring opportunities were wasted. A repeat of that profligacy could be a bigger issue when they face Argentina and France later in the pool stages.
Jones admitted that his side "lacked a bit of cohesion", but still praised his players, who face the United States in Kobe on Thursday.
"That's the second Test in a row we haven't conceded a try and that gives you a real feel of where we're at as a team," he told BBC Radio 5 Live Sport.
"We weren't sharp today but what I really liked was the attitude of our players.
"You go out with all the best intentions to be sharp, you've got a picture in your head that you're going to play some good rugby and it doesn't work out like that.
"But the good thing is we showed no frustration. The only time they got in our 22 was in the last minute of the game which gives you a show of the superiority we had."
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'Sometimes I get angry'
Jones may have admired his players' ability to control their frustration, but the England coach struggled to contain his own at certain points in the game.
The television cameras showed him slapping the table in frustration when England were caught offside in the first half.
"They never show the emotions when I smile," Jones joked. "I'm a coach, I live the game - sometimes I get angry, sometimes I get frustrated, sometimes I get happy.
"Sometimes I show it and sometimes I don't."
Fergie time helps England
As well as constant improvement, Jones said another key skill for England is patience - something former Manchester United manager Sir Alex Ferguson spoke about when he visited the side before the World Cup.
"He was renowned for, what did they use to call it? - 'Fergie time'," said Jones.
"The message was to be patient. That's what I enjoyed about our team today. We kept on playing rugby and the try comes.
"It might have been easier if it came a bit earlier but it came and that's the sign of a good team."
Jones also reported that centre Henry Slade, who was playing his first competitive match since 1 June, "just needed a bit of extra strapping" after limping off following a hefty tackle.