England centre Billy Twelvetrees is joining the British and Irish Lions' tour of Australia as cover for the tourists' injury-affected backline.
Twelvetrees, 24, has been on England duty in Argentina, scoring a try in the 32-3 win over the Pumas at the weekend.
The Gloucester man has five England caps and played four times in this year's Six Nations Championship.
He left Buenos Aires on Wednesday to fly to Sydney to join up with the Lions squad.
"I am hugely honoured to be thought of and very excited to get out there and join up with the squad," said Twelvetrees, whose mother was born in Australia.
"It is a boyhood dream. I remember the Lions in 2001 in Australia. We were going on holiday to Devon and I listened to that third Test defeat on the radio.
"The other side of my family is Australian and it is something dear to my heart. It was disappointing back then but to go out there and meet up with the squad now is pretty cool."
Twelvetrees can cover at fly-half and centre and has not been summoned as back-up for any specific player but to ease the workload of the Lions backs, head coach Warren Gatland said.
"The nature of a Lions tour means that there will inevitably be knocks which take time to recover from," said Gatland.
"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 first Test for England and he provides that versatility to cover a variety of positions."
Fly-halves Jonathan Sexton and Owen Farrell are struggling with a hamstring problem and a dead leg respectively, while centre Manu Tuilagi picked up a stinger injury in the 22-12 win over Queensland.
The Lions have already called up Ireland winger Simon Zebo as cover for Tommy Bowe and props Alex Corbisiero and Ryan Grant have also been drafted in following injuries to Cian Healy and Gethin Jenkins.
England coach Stuart Lancaster said: "All the England players and management are delighted for Billy to get this great opportunity.
"He's played well for England this year, underlined that form with his display against Argentina at the weekend and goes with our full support and blessing."