New Zealand head coach Steve Hansen believes there are up to half a dozen teams who could threaten their bid for a hat-trick of successive World Cup titles.
The All Blacks are overwhelming favourites with bookmakers to clinch the Webb Ellis Cup in Japan having triumphed in the past two editions, while their last defeat in the tournament came 12 years ago.
However, Hansen is not taking his rivals lightly as he admitted the defence of their title will be tougher than it was in 2015.
Ahead of his side's Pool B opener against South Africa, Hansen said: "It's going to be competitive – they're always competitive. It always makes me chuckle when I hear people say this side can't win or this team is going to win.
"There are a number of sides who are capable of winning it because they have the talent in the group, but with that comes higher expectation, and with higher expectation comes more pressure.
"If you don't cope with the pressure, it will overwhelm you.
"There are probably more teams who can win this tournament than the last one. In 2015, there were probably two or three; this time probably five or six, which is great for rugby."
While the Kiwis have seemed invincible for over a decade, there were some signs of weaknesses in the Rugby Championship, when they drew to the Springboks in Wellington at lost to Australia in Perth.
Asked whether he is as optimistic about his side's chances as four years ago, Hansen replied: "As confident as I can be. We've got the talent in the group to get the job done.
"It's just whether we earn the right to get all the way there. In knockout rugby, you only have to have one bad day and home you go."
Herschel Jantjies guaranteed a share of the spoils for South Africa a couple of months ago, before which New Zealand had won 12 of the last 14 meetings between the teams
Hansen said: "We've had a really good week. Preparations have been great. The boys are excited about it.
"I think we're in good shape from a match fitness point of view. Will there be nerves? Of course. If there aren't we're in trouble. Nerves are a good thing, but once the game begins I think we'll switch on and get on with it."
Hansen revealed he is pleased that captain and number eight Kieran Read is starting to become "more and more demanding".
He added: "He's an inclusive captain, he keeps his team around him, he leads from the front, and how he wants to play.
"He's starting to get more and more demanding, which I like. It's important he demands expectations. He's recovered from his back (problems) now and is really playing some good footy. He's a smart captain."