METAIRIE, La. -- New Orleans Saints reserve linebacker Chris Chamberlain is out for the season after injuring his left knee Friday night in an exhibition game against the Jacksonville Jaguars.

Chamberlain confirmed in postings on his Twitter page that MRI results from Saturday showed he tore his anterior cruciate ligament.

The linebacker says his knee buckled as he pursued running back Montell Owens during the second quarter.

New Orleans brought in Chamberlain this season as a free agent from St. Louis, where he played under new Saints defensive coordinator Steve Spagnuolo, who was the Rams' head coach the past three seasons.

Chamberlain was a starter last season in St. Louis, but in New Orleans was expected to rotate in at weakside linebacker and play on special teams.