England head coach Eddie Jones says he was pleased Japan were "fired up" by his pre-match claim that they should "pray, pray, pray".
England came from 15-10 down to win 35-15 in their penultimate autumn international at Twickenham.
Japan coach Jamie Joseph said his players were "highly motivated" by Jones, adding: "It fired me up a bit."
"That is exactly what we wanted. We wanted Japan to be at their best," Jones told BBC Radio 5 live.
"We didn't underestimate them at all. We knew it was a tough game."
"That helped us and helped our motivation."
Earlier this week, Jones told Japan, whom he coached for three years from 2012, to "go to the temple", and that England would be "absolutely ruthless".
Japan - ranked seven places below England and 60-7 losers in the teams' only previous Test meeting - led at half-time before England scored 20 unanswered second-half points.
"Perhaps we got seduced a bit by the start," said Jones, whose side led through scrum-half Danny Care's third-minute try.
"If you score with the your first touch of the ball, then perhaps players subconsciously think that this is not going to be as hard as we thought it was going to be."
|England's autumn Tests|
|3 November||Beat South Africa 12-11|
|10 November||Lost to New Zealand 16-15|
|17 November||Beat Japan 35-15|
|All matches at Twickenham|
Australian Jones, 58, said his half-time team talk was not particularly ferocious.
He said: "It's different these days. Once you get past 55, you tone it down.
"We just talked about the fact we needed more effort and needed to get stuck in. We weren't getting stuck in but started doing that in the second half.
"It's really pleasing and our players will learn a lot about that."
England made 11 changes to the team that lost 15-16 to New Zealand last weekend, and shortened their preparation time to replicate the short turnarounds involved in the World Cup.
Before the players returned to the dressing room at half-time, fly-half George Ford - captain on his 50th cap - called them into a huddle on the pitch.
"I asked the players whether that was good enough to play like that for England in a Test match and there was a resounding 'no' from everyone," he told BBC Radio 5 live.
"We needed an attitude change and a different mindset in the second half, to bring more energy and life to our performance, particularly defensively.
"The pleasing thing is we got that response in the second half."
Former England fly-half Paul Grayson on BBC Radio 5 live
If Jones' comments last week were aimed at making sure that Japan's players were as fired up as they could be, he could have said it in a better way.
If you are going to go into the depths of the World Cup, you are going to have to rely on some fringe players. When you call a team out and say you are going to stand and deliver and fail to do so, that is some cause for concern.
Former England wing Ugo Monye on BBC TV
The scoreline doesn't tell the whole story. Japan have been brilliant today; their skill level and creativity was brilliant to watch.
England's lack of fluency seemed to be down to their indiscipline. It seems to be a running theme in 2018, whether it be the Six Nations, the tour to South Africa or during these autumn internationals. They gave away almost 10 penalties in that first half offering up territory and possession.
England should not have to rely on Owen Farrell to set the bar in terms of physicality, leadership and game management. Kyle Sinckler and Sam Underhill also lifted the intensity when they came off the bench.
England dug themselves out of a hole and it's that grit that will help them in the pool stages of next year's World Cup.