England coach Steve Borthwick said he was "really pleased" that his side bagged a bonus point in their 34-12 World Cup victory over Japan in Nice on Sunday.
Joe Marchant reached out to dot down at the death to ensure England, who opened their World Cup campaign with a 27-10 victory over Argentina, took five points for the win.
"Tonight it was really tough, we got a bonus point so we're really pleased with that," said Borthwick, whose fly-half George Ford kicked 14 points to be named man-of-the-match for the second successive match.
With squad captain Owen Farrell available for the next game after serving a ban for a high tackle, and Marcus Smith enjoying a great cameo role as a replacement, Borthwick faces a dilemma for their remaining two games, against debutants Chile and Samoa, both in Lille.
"How great is it that we have such incredible depth in quality there? I think a lot of countries would want the quality we've got -- at 10 and 15. Marcus came on and was brilliant in that last quarter," said the former England lock.
England captain Courtney Lawes paid credit to Japan, who were only 10-9 down at half-time of an often scrappy contest at the Stade de Nice.
"We knew they were going to put up a fight and they certainly did that," said the flanker whose try -- England's second -- was the turning point of the match.
"The conditions are probably not as good as they look. It's so greasy out there. The boys did well, we came away with five points so you can't ask for much more."
- Tough conditions -
Lawes said hot and humid conditions had made it tough to play more accurate, running rugby.
"We wanted to play some good rugby tonight. Conditions were pretty tough to move the ball in but you saw in parts what we can do," he said.
"We'll continue to work at it and hopefully by the time it comes to the quarter-finals we'll be able to stick it. We'll need to."
England fly-half George Ford said he was "delighted".
"Japan are a great team, they challenge you in different ways, they've got an unbelievable attitude to never give in," said Ford.
"It took until that third or fourth quarter for us to pull away a little bit, which we planned for in the week actually.
"It was probably not the prettiest to watch and we had to build the game in a different way to get our points in the end, but I thought it was good discipline from the boys."
Japan coach Jamie Joseph said he had been left "incredibly proud" of his team, for whom Rikiya Matsuda scored four penalties.
"We created a lot of opportunities, we just made too many mistakes," the former All Black No 8 said.
"England put us under a lot of pressure but there were times I thought it was a real arm-wrestle, we just needed to capitalise on those opportunities and we couldn't do it.
"But that's Test rugby, they were able to wear us down."
England will now wrap up their Pool C play with two games in Lille, against Chile on September 23 and Samoa on October 7, and will fancy themselves to top the group.
Japan take on the Samoans in Toulouse on September 28 and finish off against Argentina in Nantes on October 8.