Steelers safety Troy Polamalu has, for 12 NFL seasons, been the human embodiment of Pittsburgh football.

A tough, physical, rangy safety that displayed immense athleticism, an uncanny knack for big plays and immeasurable versatility, Polamalu left his mark on nearly every game in which he participated.

These days, Polamalu is an afterthought.

Following a year beset by injuries - he appeared in only 12 games - and a postseason run that saw the longtime Steelers stalwart operate as a backup, Polamalu's time as a member of the Pittsburgh franchise could be drawing to a close, leading him to either strike out on his own in NFL free agency or hang his cleats and jersey up altogether.

"NFL Media Insider Ian Rapoport reported Wednesday that the organization believes the celebrated safety has played his last game for the Steelers, per a pair of team sources," writes Marc Sessler of NFL.com.

"Rapoport was told that the defender is not in Pittsburgh's plans for 2015 and won't be back. The only question is how his exit will play out."

The Steelers would much prefer Polamalu retire, according to Ed Bouchette of The Pittsburgh-Post Gazette.

"That is the elephant in the room," Bouchette said on The Cook and Poni Show, per CBS Pittsburgh. "I expect him not to be here by some means. The Steelers are hoping he would retire, but I don't know if he is going to."

NFL.com's Albert Breer reports that he has heard Polamalu has "expressed some desire to play in 2015" and could seek to test the waters of NFL free agency, but that those closest to the versatile safety believe he will "consider retirement if the Steelers let him go."

Polamalu, even when healthy last season, was not particularly effective - he finished the year with 61 tackles, zero interceptions, zero sacks and only a single pass defended.

For a player whose game was always built on instinctive play-making made possible by incredible feats of athleticism, this could spell a quiet end to a truly illustrious NFL career.