A person familiar with the decision told The Associated Press on Wednesday that Garrard plans to retire because of lingering knee issues.
The 35-year-old Garrard was signed in March to provide veteran competition for Mark Sanchez. But Garrard, who hadn't played in a regular-season game in the NFL since 2010 because of injuries, is planning to step away because of knee troubles.
The person spoke to the AP on condition of anonymity because neither the team nor Garrard had officially announced the decision.
NFL Network first reported that Garrard planned to retire. SiriusXM Radio host Adam Schein said that Garrard told him in a text that he had to ''call it quits'' because ''my knee is not holding up. Continuing to swell after practices. Limiting what I can do.''
The former Jacksonville Jaguars star was cut by the Miami Dolphins last summer after he needed arthroscopic surgery on his ailing left knee. Garrard was expected to be in the mix to compete for the Jets' starting job along with Sanchez and second-round pick Geno Smith. New York, which cut Tim Tebow two weeks ago, also has Greg McElroy and Matt Simms on the roster.
In a conference call with season ticket holders earlier in the day, new offensive coordinator Marty Mornhinweg insisted that the Jets starting QB job is up for grabs - and that included Garrard at the time.
''This will be a bona fide quarterback competition. Period,'' Mornhinweg said. ''I'm hoping that somebody will rise to the top quicker rather than later.''
Garrard, it now appears, will not be a part of that.
The Jets could look to add another veteran quarterback to the mix, but it appears to solidify Sanchez's spot on the roster. It was likely the team's 2009 first-round pick would remain on the Jets, mainly because he is owed $8.25 million in guaranteed money. But there was some speculation that New York could take the salary cap hit and eat the contract by releasing Sanchez - or trade him - and let Smith battle Garrard for the job.
Smith, the former record-breaking West Virginia star, was expected to be a first-round pick, but stunningly slid into the second round of the draft last month. The Jets, needing to fill several needs, surprised many by taking Smith and adding yet another quarterback to a crowded competition.
Smith said last weekend that he had spoken with the other Jets quarterbacks since being drafted, and was asked specifically about his conversations with Garrard.
''He spoke to me about just how he looks forward to competing with me, teaching me and mentoring me,'' Smith said. ''I told him, 'I'm all ears, I'm an open sponge here.' I'm just here to learn and I'm learning from every one. It's kind of like learning on the job.''
When he signed with the Jets, Garrard passed his physical with the team and said he had his sights set on having a chance at the starting job. He said he felt healthy at the time, adding that ''my knee is great now.''
Garrard had apparently been having issues with it, though. Another person familiar with the situation told the AP that the quarterback wanted to have his knee examined either Tuesday or Wednesday morning, so it had clearly been bothering him during offseason workouts.
That person, who spoke to the AP on condition of anonymity because the decision hadn't been announced, was not aware that Garrard was contemplating retirement as recently as last night.
Garrard was a fourth-round pick of Jacksonville in 2002, and became the team's full-time starter in 2007. He was selected to the Pro Bowl in 2009, but was released before the 2011 season. Garrard signed with Miami in March 2012 and appeared to be the front-runner to be the starter ahead of rookie Ryan Tannehill and veteran Matt Moore, but was released after missing the preseason with a knee issue.
He has thrown for 16,003 yards in his career, with 89 touchdowns and 54 interceptions. Garrard, also known for his mobility during his prime, has 17 career rushing touchdowns.