World Cup winner Ben Kay has rallied England for their quarter-final showdown with Australia, declaring: ''We have to perform as though our lives depend on it.''

England headed for Marseille yesterday, revitalised by successive victories over Samoa and Tonga that represented an impressive recovery from a record 36-0 defeat against South Africa.

Leicester lock Kay helped England land the Webb Ellis Trophy in Sydney four years ago.

But this time the team prepare to renew World Cup hostilities with their arch-rivals ranked as clear underdogs.

Kay said: ''We will have to be better than we have been, but every game since the South Africa match we've got better and better, so we need to keep continuing that trend.

''We know we will have to be at the top of our game to beat the Australians.

''Australia have always been the brightest team in world rugby, in terms of intelligence and knowledge of the game, and you just can't afford to make errors against them.

''They will throw something you haven't seen before at you, they will do everything very well and make the right decisions.

''There is probably a bit of satisfaction in the way the boys have responded to having their backs against the wall and fighting their way out.

''But we didn't come into this tournament just to make the quarter-finals.

''It's nice to be in the knockout stage proper, rather than having caused ourselves to be in a knockout situation two games earlier by having to beat Samoa and Tonga.

''We will be disappointed if we go home at the weekend. We've got to go out there and perform as though our lives depend on it, and I am sure Australia will do the same.

''Their record over the years has been phenomenal, particularly in the World Cup.

''But we have improved week on week from the South Africa performance. There is a feeling about the camp that everything is moving in the right direction.''

England are braced for a predictable barrage of Australian verbal banter this week in the build-up to their biggest Test since 2003.

Kay came in for some jocular treatment after he blew a certain try in the 2003 final by dropping the ball as he went over the Australian line.

But he has unstinting admiration for the Wallabies, who have twice won the World Cup and been runners-up.

Kay added: ''When I first started playing against Australia, maybe it would have got under my skin a bit, but I've got a lot of Australian mates and they are all like that! It comes with the rivalry we've got with Australia. These matches are great fun to play in because of that.

''It's a bit of paper talk that the media probably get more excited about than we do.

''I am sure I will get reminded of the dropped pass, but it happened ages ago, and fortunately it didn't have too much of a bearing on the result."

England received a double boost yesterday when Jason Robinson and Tom Rees resumed full training.

Robinson has not played since suffering a hamstring injury during England's calamity against South Africa.

Full-back Robinson sat out the victories over Samoa and Tonga, but he has now back in training alongside Rees, who was nursing a sore thigh.

Rees' fellow flanker Lewis Moody and wing Paul Sackey have been given an extra 24 hours to recover from last Friday's win against Tonga, and did not train yesterday.

Mark Cueto did rehabilitation running with the England physiotherapists as he looks to recover from a calf muscle niggle.

England head coach Brian Ashton is due to announce his starting line-up today.

Both Robinson and Rees are likely to feature in the shake-up alongside centre Andy Farrell, prop Phil Vickery and lock Simon Shaw, who could all be recalled.