Long was injured during the Rams’ 34-7 loss to the Kansas City Chiefs on Sunday. Long had the same injury 10 months ago, costing him the final game of the season.
Long, 29, was the No. 1 overall pick in the 2008 NFL draft and spent his first five years in the league with the Miami Dolphins, where he made the Pro Bowl four times and was a first-team All-Pro selection in 2010.
He joined the Rams as a free agent in 2013, signing a four-year, $34 million contract.
• NFL Week 8 coverage hub | NFL trade rumors: Latest buzz before deadline
The Rams could have two offensive linemen out of the lineup next week. Tackle Rodger Saffold left the Kansas City game in the second quarter after injuring his shoulder.
Long’s tenure with the team beyond this season could be in doubt. He is due to make $9.25 million in 2015, including $4 million guaranteed if he is on the Rams' roster on the fifth day of the next league year, according to Fox Sports’ Mike Garafolo.
Long has started all 96 games he has appeared in during his seven NFL seasons.
- Scooby Axson