Sale director of rugby Steve Diamond has revealed that Tuilagi will undergo surgery next week.
“Manu will be a loss to England and Sale,” Diamond said.
The injury means Tuilagi will miss England’s entire Autumn Nations Cup and Six Nations campaigns.
It the latest setback in a career that has been undermined by serious groin, chest and knee injuries.
“Hopefully the surgery will be next week. It’s a torn Achilles. He’ll be out for six months. It’s brutal what we’re playing at the minute,” Diamond said.
“Dan Biggar fell on him, so it was an accident. These things happen. I think it might have been of a jinx me saying before the game that we’ve got nine out of nine games out of him and boom, that happens. So I’ll keep my trap shut in future.
“Rather selfishly, after this game and the play-offs we’ll probably wouldn’t have seen Manu until April with the England commitments and EPS rest periods.”
Tuilagi was a key weapon in England’s march to the World Cup last autumn and brings irreplaceable ball-carrying prowess in midfield.
Eddie Jones does not have a like-for-like replacement and will be forced adjust the balance of his midfield as a result.
Tuilagi went down in the 11th minute of Tuesday night’s Gallagher Premiership victory over Northampton at Franklin’s Gardens after sustaining the damage while carrying out of Sale’s 22.
He had to be helped from the pitch and is now left to reflect on another lengthy spell on the sidelines so soon after leaving Leicester for the Sharks, where he had made an instant impact.
In an additional blow to England, Courtney Lawes could also be out for some time after damaging his ankle in the same match at Franklin’s Gardens.
Lawes will see a specialist next week when a time frame for his rehabilitation will be drawn up.
