The Jets placed the veteran nose tackle on season-ending injured reserve Monday with a torn anterior cruciate ligament in his left knee.
"That's hard," Ryan said. "It's going to be hard to replace Kris. There's not many Kris Jenkins playing in this league. Obviously, his impact is going to be felt."
Jenkins, a four-time Pro Bowler, was injured while making a tackle during the second quarter of the Jets' 16-13 overtime loss to the Buffalo Bills on Sunday.
"My feelings are hurt that I won't be able to be out there fighting with my teammates this year," said Jenkins, who was on crutches Monday and had his left leg heavily wrapped.
Jenkins, in his second season with the Jets, said he has "a little bit of a bone bruise on top of it." He added that the medical staff told him it would be a few weeks before the knee is operated on so he can strengthen it and regain his range of motion.
Jenkins said part of his hamstring would be used to replace the ACL. He also said that he expects to be ready for the start of the Jets' offseason conditioning programs.
"It still doesn't mean that I won't be around and it still doesn't mean I'm not a part of this team," Jenkins said. "I just won't be seen as much, which is fine because I won't have everybody commenting about my weight, so that's OK."
Jenkins, who's 30 and newly married, also said he has no plans to retire despite recently saying he has a strong desire to put his family above football.
"I'm not ready to hang the gloves up yet," he said.
Jenkins tackled Bills running back Fred Jackson on a 4-yard run with just over 5 minutes left before halftime and went down as Jets teammate Shaun Ellis rolled into him in the pile, grimacing while laying on his back. Jenkins slowly walked off the field to the sideline before heading to the locker room.
"I'm balanced now," he said with a smile.
Jenkins said he knew something was wrong as soon as he went down with the injury.
"I've been through the experience once, and you know what that pop is when it happens," he said. "It was a little bit different this time, as compared to the first one because the first time it was just a clean pop, bad position and it went on its own. This time, I don't know what happened, but I know I took a blow to it."
Jenkins added that he didn't blame Ellis for his injury.
"I know that Shaun plays hard like I do," Jenkins said. "Sometimes when you're in the pile, stuff happens. I hope he is not taking it hard. I hope he's relaxed about it because it could have happened to anybody."
Jenkins rejuvenated his career after a sometimes tumultuous seven years in Carolina. Jenkins was moved from defensive tackle to nose tackle in former Jets coach Eric Mangini's 3-4 scheme and thrived, making his fourth Pro Bowl. He performed in a similar role in Ryan's system and often was dominant -- routinely taking on two blockers -- in the Jets' rushing defense.
"If this was the first time that I would have went through something like this, then it probably would be tough," Jenkins said. "But this is something that I've understood over time. It comes with the game."
Copyright 2009 by The Associated Press