Cipriani made 13 tackles against the Pacific Islanders last Saturday
England's Danny Cipriani has been told to "front up" in defence if he is to become the best fly-half in the world.
The precocious 21-year-old is widely regarded as one of the most gifted attacking players in the game.
But England defence coach Mike Ford believes Cipriani also needs to prove he can defend, starting against Australia at Twickenham on Saturday.
Ford said: "He might as well get that part of his game right both physically and mentally - and he's doing that."
Cipriani and half-back partner Danny Care are expected to be severely tested in defence by the powerful midfield running of Stirling Mortlock and Ryan Cross.
Ford conceded Australia talisman Mortlock would attempt to "dent our defence".
He added: "Danny wants to be one of the best players in the world and he realises one of the responsibilities of a fly-half who wants to be number one is that he has got to defend in that channel.
Cipriani's obviously got a very good kicking game, he directs play very well and he's an elusive runner
"If we hide someone in defence and the opposition don't get him in the first phase, they will get him second. My experience at international level is that they will find him out.
"We understand that and Danny does as well. Cipriani made 13 tackles against the Pacific Islanders at the weekend so we know he can tackle."
Australia outside-half Matt Giteau, a player Ford described as a "magician", believed Wasps star Cipriani, starting his third international, posed a major threat to the visitors.
"He's obviously got a very good kicking game, he directs play very well and he's an elusive runner who can pass the ball very well on both sides," said Giteau, who made his international debut aged 20 at Twickenham in 2002.
"A lot of their attack rolls around their nine and 10, like most sides. So I think he's very pivotal on how the side plays and I'm looking forward to playing him."
Asked whether he has a particular plan to stop Cipriani, Giteau joked: "I do, but I won't be telling anyone. Maybe after the game I'll say whether my plan worked or not.
"They've got a new backline and they look like they love to attack, so that's something we need to be wary of."
Meanwhile, England captain Steve Borthwick admitted his team needed to be at their best if they stood any chance of beating Australia.
Borthwick, who led his country on home soil for the first time last weekend as England defeated the Pacific Islanders 39-13, said: "This is a huge challenge.
"The battles between England and Australia are always hard-fought. It is one that is really exciting.
"The Pacific Islanders was a big contest. They were certainly one of the biggest teams I have played against.
"That was a great start for us but we need to get better. We know Australia are up there with the best teams in the world.
"We know every one of us will have to reach the final percentages of our ability. England have got a lot of strengths."