England manager Martin Johnson is warning his side to beware Georgia after hailing the standard of what he called one of the "best weekends of pool games in World Cup history".
Although there were no upset wins, Romania, Namibia and Japan all punched above their weight before losing to Scotland, Fiji and France respectively, while Ireland were made to work hard for a win against the United States.
Previous World Cups have seen blow-outs such as Australia's 142-0 thrashing of Namibia in 2003 and New Zealand's 145-17 rout of Japan in 1995.
England, runners-up in France four years ago, scraped to a 13-9 win on Saturday over an Argentine side that upset the odds to finish third in 2007.
England's next Pool B match is against Georgia, who begin their World Cup campaign against Scotland on Wednesday.
Four years ago, the eastern Europeans came close to causing a major shock before losing 14-10 to Ireland, and Johnson said the weekend's results had confirmed his long-held belief in the rising standards of rugby worldwide.
"The weekend showed what we've been saying - this is a battle," Johnson told reporters at England's hotel in Queenstown.
"It was one of the best weekends of pool games in World Cup history," added England's 2003 World Cup-winning captain.
"There's a bit of criticism gone around in the past about meaningless games in the pool but you know what's happened at the weekend.
"Everyone's got to fight. These teams are well organised. Their players play professionally in Europe or wherever they are - they're organised.
"It's not turn up and score 50, 60 points any more," the former lock insisted. "It's harder than that and we've seen it.
"If you get to terms with that mentally - we're going to be in a battle and we need to fight for every inch - you're in a good place because that's what we had to do on Saturday and that's what we need to do this Sunday to get on top of another team. That's a fundamental of the game."
Johnson said host New Zealand's 41-10 win over Tonga, where the All Blacks were 29-3 ahead at halftime, had been the exception that proved the rule.
"New Zealand were so composed and so slick out wide - I thought Tonga defended a lot better in the second half - they got themselves the comfort of that lead and they had won the game by halftime, I think," he said.
"But no one else had over the weekend. Look at Wales-South Africa (which the reigning champion Springboks won 17-16 on Monday). What a game that was.
"We've been telling you it's like this and now you're telling me.
"If you look at the weekend's games, every winning coach said 'I'm glad to get the win but we have to improve, and every losing coach said 'it was so close'. I know where I'd rather be sitting."