Saints have confirmed that South Africa ace Heinrich Brüssow will be the man to fill the void left by Louis Picamoles at Franklin's Gardens.
Brüssow will move to Northampton in January, following the completion of his commitments at Japanese club Docomo Red Hurricanes.
The 31-year-old has been capped 23 times by his country and made a big impression against the British & Irish Lions in the 2009.
Brüssow amassed considerable amounts of experience in Super Rugby, playing for the Bloemfontein-based Cheetahs.
He will not be a direct replacement for Picamoles as Brüssow's skills predominantly lie in the seven shirt.
But his arrival will bolster the back row, with Mitch Eadie and Teimana Harrison continuing to compete for the No.8 shirt.
Sam Dickinson, who rejoined Saints on a short-term deal before the season started, will depart after Christmas.
“Heinrich has shown his class year in, year out, and we’re delighted that he has decided to join us,” said Saints boss Jim Mallinder.
“He has plenty of experience and our younger players will learn a lot from him, especially from his play at the breakdown.
“After the sudden departure of Louis Picamoles we have been looking for the right player to add to our squad, both in terms of quality, experience and character, and we believe that Heinrich is the right person to bring to Franklin’s Gardens.
“We’re looking forward to him joining us later in the season.”
Brüssow can't wait to get started at Saints.
He said: “After five seasons in Japan, my wife and I feel it is time for a new challenge.
“I feel humbled to be afforded the opportunity to join a club with such a rich history and traditions.
“Franklin’s Gardens is one of those special places you hear some of the best players in the world talk about and the thought of representing a team like Northampton Saints is something that excites me immensely.
“I am looking forward to learning from new coaches, team mates and getting know and experience everything Northampton has to offer.
"The reputation of the Saints as a team speaks for itself and I want to play my best possible rugby and hopefully contribute to winning a few trophies.
“The last couple of years in Japan have been really special in terms of experiencing a totally different environment, culture and a unique style of rugby in a unique league.
"I have definitely grown as a person and as a player and will always be grateful for the way NTT Docomo and the people of Osaka welcomed and supported myself and Caroline during our time here.”