Garrard knee bone-on-bone Dan Leberfeld

Former Jets quarterback David Garrard, who told friends in the media he’s retiring, has bone-on-bone in his bad knee.

Garrard told Sports Illustrated’s Peter King, who covers the NFL and politics for the magazine, that his bad knee doesn’t have much cartilage left, so there is bone-on-bone friction.

“I couldn’t jog most days,” Garrard told King. “I could barely walk around without it hurting. And we weren’t even in the strenuous part of camp yet. I figured, ‘No way I can just take every fourth day off.’ I went to see Rex [Ryan], and I just told him I didn’t think I could do it. He didn’t want to hear it. But I just told him what the doctor said — it’s only going to get worse. And that was it.”