Johnson wary of Pumas

The Pumas, who face England at Old Trafford this afternoon, may have lost five of their last seven matches since finishing third in the 2007 World Cup but they still sit one place higher than England in the International Rugby Board rankings.

"If they think there's a weakness in you they'll exploit it. They're a very hard team to score against and beat," he said. "I admire the way they play. They're right in your face and they come after you."

He added: "They're a good team with guys who play at the highest level around Europe. They're not number five in the world by accident.

"You don't end up coming third in the World Cup and getting out of the pool they got out of without winning Test matches.

"If we hit the level of performance we're capable of then we have a chance of winning."

England's only previous visit to Old Trafford was their eventful 25-8 defeat by New Zealand in 1997 - Sir Clive Woodward's second match in charge.

Johnson received a one-Test suspension for punching Justin Marshall while hooker Richard Cockerill famously eye-balled All Black hooker Norm Hewitt during a highly-charged Haka.

"Old Trafford are different surroundings but guys play on football pitches a lot in the Premiership," said Johnson. "It's a lot tighter than Twickenham in terms of where the stands are. The dead-ball area is a lot smaller as well.

"I enjoyed '97 when we came up here and it's great for people up here to come and watch England without having to travel all the way down there. People will come who haven't seen England play before and that's good."