Jim Leonhard will be a sidelined spectator for another Jets playoff push.

The playmaking safety will miss the rest of the season after being placed on injured reserve Monday with a torn patellar tendon in his right knee. An MRI exam confirmed what the Jets first feared when Leonhard went down on a tackle following an interception in Sunday's 37-10 victory over the Kansas City Chiefs.

"You feel absolutely terrible for him," coach Rex Ryan said.

It's the second straight year Leonhard has been lost for the season because of a devastating injury. Leonhard broke the same leg in a collision with teammate Patrick Turner during practice a little more than a year ago.

"This team means everything to Jim, and his leadership is going to be missed without question," Ryan said. "He's one of the guys that elevates other players around him."

On Sunday, Leonhard was hurt when he intercepted a pass by Tyler Palko intended for Steve Breaston, and the Chiefs wide receiver grabbed Leonhard's leg for the tackle. He went down and immediately grabbed at his leg and needed help from two trainers to walk off the field before being carted from the sideline to the locker room.

Center Nick Mangold said the players' emotions at the team's facility were "kind of mixed" despite the big victory because of the news regarding their teammate.

Leonhard will need to wait for the swelling to subside before having surgery, and then Ryan hopes he might be able to be around the team in a player-coach role as he was at the end of last season.

Veteran Brodney Pool will step into Leonhard's starting spot alongside Eric Smith, and Ryan indicated that the team will look to bring add some depth at the position. Pool, re-signed in the offseason, is a former starter who has two years of experience in Ryan's defense and played well last year, particularly in the playoffs.

"He and Eric Smith had one of the best postseasons I've seen by any type of safeties from those two guys," cornerback Antonio Cromartie said.

Cromartie added that Leonhard was "in good spirits right now" when he saw him at the team's facility.

Leonhard is one of Ryan's favorites, a player whom the coach brought with him from Baltimore when he took over in New York in 2009. Leonhard is in the final season of his three-year deal with the Jets, so it's uncertain whether he has played his last game in New York. Ryan insists Leonhard will rebound from this latest injury, though.

"This is a setback," Ryan said. "This is not going to be the end of Jim Leonhard. I don't think Jim Leonhard is done playing."

Leonhard had recently reassumed the primary punt return duties, which will now go back to rookie Jeremy Kerley. The 29-year-old safety finished with 60 tackles and an interception this season.