Court, currently in his home city of Brisbane after Ireland's tour of North America, comes in following a calf injury to Alex Corbisiero that continues to be treated and assessed.
The Ulster forward will join up with the squad tomorrow and go straight on to the replacements' bench for Tuesday's game against the RaboDirect Melbourne Rebels in place of Makovina Vunipola, who has been withdrawn.
Lock Paul O'Connell suffered an arm injury in the 1st Test against Australia and continues to be treated and assessed.
British & Irish Lions Media Manager
Australia Tour 2013
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