Leicester's Thomas Waldrom has been officially called into the England squad in place of prop Andrew Sheridan.
Sheridan injured his left shoulder in the opening match against Argentina, but England boss Martin Johnson had kept his options open until now.
"If I get an opportunity to play it will be a very big honour and my family will be very proud of me as well," said the 28-year-old.
"It's a big turnaround. I'm pleased to grab it at this stage of my career."
Uncapped back rower Waldrom had been in New Zealand since Wednesday after being called up as cover after number eight Nick Easter injured his back.
England are hopeful Easter will recover to play some part in the tournament.
Prop Matt Stevens also has an ankle problem after getting a knock in the Georgia win.
Johnson decided to stick with four props in his 30-man squad and strengthen England's back row options with the inclusion of Waldrom.
"Nick is making good progress as is Matt Stevens but with Thomas now out here it makes sense to get him into the squad officially so he can join in with training," said Johnson.
"We also owe it to Leicester to make a decision so that they can plan accordingly without him."
Waldrom had played in Leicester's first three Premiership games before being called out to New Zealand.
The 6ft 1in, 17st 6lb number eight was part of England's extended World Cup preliminary squad.
The New Zealand-born Waldrom qualifies for Johnson's team because of an English grandmother, but he played for New Zealand Under-21s and New Zealand Maori.
Last season, his first in England, Waldrom was named the Premiership players' player of the season.
Waldrom, who is regarded as a mobile number eight with good skills, played for the Hurricanes and the Crusaders in the Super 14 before moving to England.