Wasps player Launchbury went to Christ’s Hospital and played for Horsham and Barns Green before joining the Harlequins Academy at the age of 15. He also played for Worthing Raiders in the 2009-10 season.
Joe Marler started his career at Haywards Heath Rugby Club where he played in the same side as Twelvetrees. Marler also played for Worthing.
Twelvetrees grew up in Wisborough Green and attended The Weald School in Billingshurst.
All three were in the provisional squad but Twelvetrees did not make the final 31.
The Rugby World Cup takes place from September 18 to October 31.
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