Garrard told SiriusXM NFL Radio on Thursday that his surgically repaired left knee kept swelling up on him after workouts, and that forced him to walk away from the game and consider retirement.
"I'd get four or five days of good work on it in, and then the next two days it is swollen and I have to do everything I can to get the swelling out," Garrard said. "Start the next week over and it would just be the same process every time, and so it was never just allowing me to just go on and just play without any worries.
"So I just kept thinking: 'How am I going to compete for the starting job if every four days I've got to stop and have an ice bag on my knee while the guys are practicing?' "
Garrard, 35, was signed in March to provide veteran competition for Mark Sanchez. But Garrard hadn't played in an NFL regular-season game since 2010 because of injuries. The former Jacksonville Jaguars star was cut by the Miami Dolphins last summer after he needed arthroscopic surgery on his knee.
But Garrard was feeling healthy this offseason and passed his physical with the Jets. He was expected to compete for the Jets' starting job with Sanchez and second-round draft pick Geno Smith. New York, which cut Tim Tebow two weeks ago, also has Greg McElroy and Matt Simms on its roster.
"My knee just never really quite got back to, not to where it was before, but not even just well enough to, it was well enough to get out and run around and stuff, but it would still swell on me," Garrard said. "I thought, 'I look pretty good right now. Maybe if I get on with the team, the treatment that they have there, the round-the-clock treatments you pretty much get, that should probably help me out.' So that's how I was thinking."
Garrard also was asked if the Jets drafting Smith played any role in his decision.
"Oh, no, it didn't play into it at all," Garrard said. "I was in Miami last year when they got (Ryan) Tannehill in the first round, Blaine Gabbert in the first round (in Jacksonville). So I've been through that before. That wasn't an issue at all. It was really just my knee and my health."
Despite not playing for the Jets, Garrard could be around the team this summer. He said the Jets offered him "a little bit of an internship" in which he could work with the team's quarterbacks at training camp in Cortland, N.Y. Garrard said he would consider that, as well as finishing his degree and pursuing a radio or TV gig as a football analyst.
"I'm very blessed and very fortunate that I am able to walk away from the game without any real crazy injuries," he said. "The future is still bright."
Copyright 2013 by The Associated Press