David Strettle has withdrawn from England's World Cup squad to move to France and will be replaced at their training camp by Semesa Rokoduguni.
Strettle, 31, who won the Aviva Premiership with Saracens last month, is set to join French heavyweights Clermont Auvergne ahead of the new Top 14 season.
Rather than take part in England's World Cup preparations, the wing opted to withdraw from Stuart Lancaster's squad before it assembled on Monday, in order to start the process of resettling his family in France.
Strettle said: "The opportunity to join Clermont and the subsequent decision to leave Saracens obviously was difficult and not one I have taken lightly.
"Having now committed to a three-year move at what I feel is the right time in my career and for my family, I would like to begin that challenge right away.
"With the England training camp beginning this week, I wanted to be fair to Stuart and the rest of the squad before that started. It goes without saying that I wish England the very best for the tournament and I will be supporting them all the way.
"I am extremely proud to have represented England and will look fondly back on the 14 caps I have won for my country since 2007."
England head coach Lancaster was disappointed but understanding. He said: "Clearly a lot has been going on with David recently with the late interest from Clermont and his decision to leave Saracens.
"After visiting France recently and discussing it with his family, he has made the decision to move early to get settled before the season in France starts.
"Obviously, it is disappointing but David and I have chatted and he feels that, having made the move, he wants to get on with forging his new career and we both agreed it was the best course of action for him to withdraw from the squad. We all wish David and his family well in France as they begin a new chapter in their lives."
Bath wing Rokoduguni, who is flying back from Fiji to join up with Lancaster's squad, made his England debut against New Zealand during last year's Autumn internationals.
"I'm delighted to have been given the opportunity to join England for their World Cup training camp," said Rokoduguni. "It's a huge privilege and I'm really looking forward to meeting up with the boys."