The 29-year-old was called up to Warren Gatland’s Six Nations squad earlier this year but now faces knee reconstruction surgery once the swelling has subsided.
Lewis-Roberts, born in Denbighshire is the heaviest player in the English Premiership at 132kg, made his Wales debut against Canada in 2008 during this Autumn international series.
“It’s not looking good for Eifion, he’s done his ACL,” said Sale director of rugby Mike Brewer.
“We need to get the swelling down over the next week or so and he will then need knee reconstruction surgery.”
