The England and Gloucester Rugby centre will fly from Argentina today (Wednesday) and arrive in Sydney on Friday.
British & Irish Lions Head Coach Warren Gatland said: "The nature of a Lions tour means that there will inevitably be knocks which take time to recover from. The whole squad have worked hard but a lot of the backs have doubled up over the last two games, either starting or from the bench. Billy played well in the 1st Test for England and he provides that versatility to cover a variety of positions."
British & Irish Lions Media Manager
Australia Tour 2013
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