Kieran Longbottom, the Western Force prop forward, has agreed to join Heineken Cup and Premiership finalists Saracens.
The 28-year-old, Australian by birth but eligible to play for England, has produced a series of outstanding performances in the current Super Rugby season.
"We are delighted that Kieran and Brigitta have decided to come to London," said Saracens director of rugby Mark McCall.
"He has shown up consistently well in our scouting reports, and he will prove an outstanding addition to the squad."
"Saracens are recognised as one of the go-forward clubs in Europe, and I'm really looking forward to this opportunity," said Longbottom.
Longbottom had been tipped for a call-up by Australia for the series against France, but his agreement to play overseas in England ruled him out of contention.