La Rochelle - Former New Zealand lock Jason Eaton on Thursday announced his retirement from rugby at the end of the season as he struggles to recover from concussion, according to his Top 14 club La Rochelle.
Eaton, 35, suffered the injury playing against Clermont early last month and has taken the decision to retire because his condition is "not really improving as much as I'd like".
"It's obviously not the planned finish I wanted," Eaton told a press conference at his club on Thursday.
"But that's the nature of the sport. I can't control injuries... because I'm retiring I'll put more importance on my brain because I'm going to need it pretty soon.
"It's pretty easy to run around a rugby field without a brain, but to work in an office or whatever it is, it's pretty important."
Eaton, who made his name while playing for the Hurricanes in Super Rugby, also played in Japan with Shining Arcs before joining La Rochelle in 2014, going on to become the French side's captain.
La Rochelle finished in the top six of the 14-strong league for the first time last season, and qualified for their first European Champions Cup before losing in the quarter-finals to Welsh side Llanelli Scarlets.
Eaton is as yet unsure whether he will play in La Rochelle's remaining games this season.
What is even less certain for the former All Black, who played 18 times for the world's greatest national rugby team, is what the future holds.
"I've no idea what I'm going to do work-wise, I'm pretty sure it's not going to be in rugby," added Eaton.
"I'll move into some other sector, I don't know what yet. It's going to be a new and challenging time."