6:21pm: The Lions released a statement that doesn’t deny the ESPN.com report but doesn’t close the book on Johnson’s career with the team, either. “Regarding today’s ESPN report, we stand by our statement issued on Jan. 6 regarding Calvin,” the team’s comment reads, according to Tim Twentyman of Lions.com (on Twitter).

The team is standing by its previous stance of Johnson’s retirement not being final, which read, per Twentyman (Twitter links), “We obviously have profound respect for Calvin and certainly understand and appreciate his decision to give proper thought and consideration to his football future.”

4:22pm: Lions receiver Calvin Johnson told a group of family and friends prior to last season that 2015 would be his final year in the NFL, and he relayed that same sentiment to head coach Jim Caldwell following the conclusion of the regular season, sources tell Adam Schefter of ESPN.com. Detroit management has not given up hope that Johnson will change his mind, but a person close to Johnson said the receiver is “pretty content with his decision,” per Schefter.

After Johnson told Caldwell of his plans, the Lions head coach reportedly asked Johnson to take his time to mull over the decision, and out of respect for Caldwell, Johnson did just that, according to Schefter. Only two of of Johnson’s teammates — quarterback Matthew Stafford and linebacker Stephen Tulloch — were told of Johnson’s retirement thoughts prior to the 2015 season, and they were asked to keep the decision under wraps. No one else in the Lions organization learned of Johnson’s aims until the end of the season.

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When the rest of the franchise learned of Johnson’s intentions, reports did start to leak out, and an early January report indicated Johnson was indeed mulling hanging up his cleats. Johnson downplayed the specifics of that report, however, indicating that he was still thinking through his options. “Like many players at this stage of their career, I am currently evaluating options for my future,” Johnson said at the time. “I would expect to have a decision regarding this matter in the not-too-distant future.”

According to Schefter, the wear and tear of nine seasons in the NFL has done a number on Johnson, who has been dealing with nagging ankle injuries and overall soreness (he’s also deal with finger issues in recent years). Megatron has been remarkably durable — he’s missed just five games of the past five seasons — but heading into his age-31 season, it seems that physical ailments have taken their toll.

If Johnson does retire, he will owe the Lions $3.2MM in signing bonus money, as Mike Florio of Pro Football Talk notes (Twitter link). Moreover, Detroit will save more than $11MM on its 2016 salary cap if Johnson hangs it up. Even if he does reverse course and decide to play another year, Johnson and the club might have to rework his current deal, and his cap charge is set to balloon to more than $24MM next season.

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Since leading the NFL with 122 receptions and 1,964 yards in 2012, Johnson has seen his production decline a little. Still, he continued to be one of the league’s more productive pass catchers in 2015, with 88 catches, 1,214 yards, and nine touchdowns. Johnson is the Lions’ all-time leader in receptions (731) receiving yards (11,619) and receiving touchdowns (83), tweets Dianna Marie Russini of ESPN.

As of last week, new Lions general manager Bob Quinn said he had not spoken to Johnson about his future, though Quinn did note that he hoped to have a resolution before the start of free agency in March.

Photo courtesy of USA Today Sports Images.