The 24-year-old brings to an end a two-year spell in Glasgow where he made 22 appearances for the Warriors.
Alainu’uese will certainly add considerable bulk to Toulon’s pack, weighing in at 138kg and towering at 2.07 metres.
The 24-year-old played five times for Samoa’s Under 20’s, scoring one try.
Rennie reflected on the reasons to allow Alainu’uese to move to France: “It’s a decision that’s in the best interest of both the player and the club.
“Brian’s had a number of injuries over the last couple of years and we’ve not been able to play him as often as we would have liked, but he’s a good man, is very popular among the squad and will be missed.
“When he’s fit and firing he’s an excellent player and we wish him all the best in France.”
Glasgow Warriors Managing Director, Nathan Bombrys, added: “This move gives Brian an opportunity to secure a longer-term contract and will allow us to strengthen our squad in other key areas.”
Brian Alainu’uese, said: “I’ve really enjoyed my two years in Glasgow. They’re a good bunch of boys and everyone made me feel very welcome. I hope the club goes on to have a lot of success in the future.”
Toulon have had a poor start to the season, they’re third from bottom in the Top 14 with just two wins and from their seven matches so far. They are also bottom of Pool 5 in the Heineken Champions Cup having lost at home to Newcastle Falcons in the opening round, followed by a 40-14 thrashing at the hands of Edinburgh.
Meanwhile, Glasgow Warriors have agreed to an early release for Lead Strength and Conditioning Coach, Phil Healey to return home to New Zealand for personal reasons.
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