NEW YORK (Reuters) - New York Jets nose tackle Kris Jenkins has been sidelined for the rest of the season after re-injuring his left knee against the Baltimore Ravens on Monday.

The 31-year-old tore the anterior cruciate ligament after being caught in a pileup following a three-yard run by Ravens fullback La'Ron McClain in the first quarter.

"I just feel really bad for Kris, a guy that rehabbed that injury every day and worked at it. We lost a heck of a football player. We just have to step up."

Jenkins tore the same ACL against the Buffalo Bills in the sixth game of 2009 and made his first regular season appearance since then against the Ravens on Monday.

His absence will be sorely felt by the Jets, who lost their season opener 10-9 to Baltimore after receiving plenty of attention during the off-season for appearing on a reality show and talking up their Super Bowl chances.

"Just a big powerful man who is athletic and hard to block one-on-one, impossible really."

Ryan added that surgery had not yet been scheduled for Jenkins.

(Writing by Mark Lamport-Stokes in Los Angeles; Editing by Steve Ginsburg)