The 24-year-old injured his knee just before the halftime break during the 18-14 loss to Northland in Whangarei on Sunday.
Stags coach Dale MacLeod said they were waiting on a scan but the powerhouse second-rower has a suspected torn medial collateral ligament and faces from three to six weeks on the sideline.
Six weeks would effectively rule him out for the remainder of the season but MacLeod remains hopeful he still has a role to play in the campaign.
"It is not too good but it does not require surgery at this stage,"
MacLeod said.
"But it could be three to six weeks — we are just waiting on a little more feedback on it.
"He certainly won’t feature for at least three weeks ... and possibly the season.
"But we are still holding out hope. He is a tough, resilient character ... and he has proven in the past when he has had some niggles and bangs that he is pretty resilient.
"He has a big engine and just goes all day ... but we know the guys will come in and do a job."
Southland was ahead in most of the key game statistics except where it counted the most in its narrow loss to Northland.
He felt his side got "tunnel vision" while attacking and it was a matter of "taking a little breath" and improving its composure.
"There is nothing major. It is all just simple fixes and we just need a little more attention to detail by individuals and we would have won that game 99 times out of 100.
"We are all gutted by an opportunity which we let go."
Southland will host Taranaki on Saturday evening. It is expected to name its side tomorrow.