Robinson is to undergo an arthroscopy to clear out "minor debris" from the right knee he damaged in England's first Test defeat to South Africa on May 28.

England's management are confident Robinson's World Cup is not in danger and they expect the 32-year-old winger to be available for the August Test programme.

England warm up for their World Cup defence by facing Wales at Twickenham on August 4 before tackling tournament hosts France home and away.

But England must name their final 30-man World Cup squad on August 14, in between the two France Tests.

Ashton is already sweating over the fitness of Mike Tindall and Dan Ward-Smith and the last thing he will want is a further headache over Robinson's fitness.

Robinson, who will retire from rugby after the World Cup, is thought to be in a small group of players guaranteed to be included in Ashton's final squad.

That would be unlikely to change even if Robinson misses the three August Tests - providing he is fit for the World Cup - but it would certainly throw a spanner in the works.

Ashton is running out of time to gel a side and he could want Robinson available to play Wales just four weeks after he goes under the knife.

The South Africa tour threw up a few new contenders for the wider England training squad - the likes of hooker Mark Regan in particular - which Ashton will name next Friday.

But it did little to help him formulate the England team as a cohesive unit ahead of their World Cup defence, which makes the August programme all the more important.