England pose biggest threat - Henry

Richie McCaw catches the ball during a test against England at Eden Park this season. Photo / Getty Images

In front of a packed and partisan crowd, World Cup-winning coach Sir Graham Henry believes England pose the biggest roadblock to the All Blacks winning back-to-back titles.

Henry, who will host a supporters' package to the World Cup in England next year, along with unlikely 2011 hero Stephen Donald, said you should not underestimate the power of a home crowd, both in lifting spirits and influencing officials.

He described the effect of England playing at Twickenham as similar to the All Blacks' mastery at Eden Park, and also believes referees become susceptible to pressure from 70,000 home supporters at rugby HQ.

"England playing at home give away [an average of] eight penalties a game," Henry said.

"Playing away they concede 16. There will be some rugby reasons for that ... but most refs tend to favour the home side. I don't believe it's intentional, it's more a subconscious thing. You've at least 70,000 English people pressuring you to make decisions that favour their side."

Despite losing the June series 3-0 to the All Blacks, England, for the first two tests at least, showed they were making significant progress under coach Stuart Lancaster, particularly with regards to playing with width.

They will not, however, be the only side capable of mounting a genuine title challenge.

"Ireland will be competitive," Henry said. "Joe Schmidt is a very good coach. They will be focused and play to their potential. My worry with them is fitness. They tend to run out of petrol."

South Africa's competitiveness in Wellington last weekend caught the eye of Henry, and one player in particular impressed the coach. While acknowledging that the better side won, he saw enough from the Boks to suggest that they could be competitive next year if they get everything right.

"The young first-five, Handre Pollard, has real ability," Henry said.

"He has natural talent and can play in traffic.

"He kicks goals, he kicks long goals and can hit drop kicks.

"That try they scored [in Wellington], I don't think they can do that without him there."

New Zealand's old friends from across the Ditch also warrant a mention, not so much because they showed with a 12-12 draw in Sydney that they can run the All Blacks close on an off-night, but because of the players still to come back into the fold.

"You've got Will Genia, Quade Cooper, the hooker Stephen Moore and Henry Speight on the wing. Those guys will give them some authority, because that's what they're lacking at the moment."

Henry said that Pool A, which contains Wales, Australia and England, was so strong that the two teams that emerge from that will be much better prepared than the All Blacks who have a super-soft pool.