Frank Lampard and John Terry have both insisted that England still have work to do if they are to reach South Africa 2010.

England scored twice in each half on Saturday to claim a 4-0 win in Kazakhstan and their sixth straight World Cup 2010 qualification success.

Gareth Barry celebrated his £12million switch to Manchester City by nodding home a 40th-minute opener and Emile Heskey tapped home a second on the stroke of half-time. England were in cruise control after the interval and further goals from Wayne Rooney (72) and Lampard (penalty, 77) put the gloss on a comfortable evening's work for Fabio Capello's side.

Despite their success, Lampard applauded a "professional" job by England, but recognised the team had taken a while to get started.

"We had to get our heads down and work hard this week and focus on this game," Lampard told Setanta 1.

"It took us about 20 minutes or half an hour to get going but then we won comfortably.

"I think it was professional, there were things we could have done better.

"We are on a confident run and we need to keep it going. We've taken a big step again.

"Our main objective is to qualify, the sooner we do that the better."

Skipper Terry insisted England "are not there yet" despite their perfect record.

He said: "That is a massive win on the way to where we want to be. It really is a big win.

"It was a difficult game. We knew that was going to be the case. For the first 40 to 50 minutes, I thought they worked really well, but after that they seemed to tire.

"We came into our own and kept the ball a lot better in the second half. It was a great performance in the end.

"It was a good way to continue our impressive start to the campaign, and six wins out of six is fantastic.

"But we're not there yet, we're in a good position, but taking nothing for granted. We've got Andorra at home, and they can sit back and make it difficult. But if we can get the seventh win out of seven, it will be fantastic."

Terry knows from past experiences that England cannot afford to take anything for granted, even though it will be a major surprise now if they do not qualify for the World Cup finals.

He said: "I think the expectation is still there. I wouldn't say a big weight has been lifted because that pressure at international level is always there.

"It's the same even in games like this. Everyone expects us to turn them over easily. Sometimes that is not the case.

"We went to Andorra last year and found it difficult, and teams are getting a lot wiser, knowing how to play against the bigger teams, and making it difficult for us.

"But we are playing really well - and are on the way to where we want to be."