England will meet an American pack prepared by one of New Zealand's top technical coaches in their World Cup pool match in Lens tomorrow.

The United States believe an emphasis on forward play presents their best chance of keeping England in check and have developed their game plan accordingly with the help of the forwards expert Mike Cron.

Bill LeClerc, the US scrum coach, explained: "We have come a long way in a very short time. We were fortunate to have worked with Mike Cron from the New Zealand Rugby Union, and we have implemented a lot of his techniques.

"Many of our players have come along in leaps and bounds in terms of their conditioning. They are up for it, and they want to see how they go against one of the best packs in the world."

Mike Hercus, the former Sale and Llanelli fly half, will lead the US, while Paul Emerick, the Newport Gwent Dragons centre, offers a strong midfield presence. The highly rated No 8 Henry Bloomfield and winger Takudzwa Ngwenya will make their Test debuts.

Peter Thorburn, the US head coach, said: "He [Bloomfield] is a very big boy - I wouldn't like to be paying his food bills! He is 300lb and, like a lot of American players, is coming to the game late in life.

"He has worked extremely hard over the last 12 months to improve his conditioning, as have the whole squad, but he is a good example of the work that has gone on.

"Takudzwa is an exceptional talent. He's got something you can't coach, and that is real speed, and he also has good evasive skills. He is not a big kid, but he is quite strong."

Realistically, the US will do well to restrict England to score of a less than 50 points. They lack the overall pace and power to make it a genuine contest, and their final warm-up game saw them beaten by a second-string Munster outfit in Chicago.

Thorburn said: "Of the players available, it certainly is a full-strength team. We are obliged to put the best players on the field for these games. We owe it to the rugby public to play our best stars."