It's not really possible to replace a one-of-a-kind player.
Pittsburgh Steelers safety Troy Polamalu, a guy who, over the course of a 12-year NFL career, amassed 581 tackles, 32 interceptions, 14 forced fumbles, one AP Defensive Player of the Year award, four first-team All-Pro selections and eight Pro Bowl nods, was very much one of those players.
Now that the future Hall of Famer and human embodiment of the notion of "playing with your hair on fire" has called it a career, the Steel City is left with few options to even adequately fill the gaping hole left by his departure.
One of the guys tasked with that mammoth undertaking, Shamarko Thomas, knows the difficulty he and the rest of the Pittsburgh defense will have making up for Polamalu's retirement.
''I'm definitely sorry that Troy's gone, and I can't replace him,'' Thomas said, via Dale Grdnic of The Associated Press. ''He's a Hall of Famer. I'm not worried about the job right now. I'm just out here trying to compete and trying to get involved with my team and just working hard.''
The Steelers took Gerod Holliman out of Louisville in the seventh-round of April's draft, but he'll likely have an opportunity to back-up free safety Mike Mitchell early in his NFL career. Will Allen represents another option to replace Polamalu's prodigious on-field production - production that had admittedly been dwindling as Polamalu struggled to stay healthy in recent seasons - but Thomas is the younger and more physically gifted of the two.
Thomas, a fourth-round pick for Pittsburgh GM Kevin Colbert in the 2013 NFL Draft, hasn't made much of a name for himself thus far into his two-year career - he's got all of 34 tackles and two forced fumbles in 25 appearances and played solely on special teams last year - but he spent this offseason working and training with Polamalu in the hopes of catching some of the greatness his former Steelers backfield mate displayed during his own career.
''That was a great experience for me, and I kept up doing the explosive stuff, plyometrics, all the things to keep me explosive, coming out of my breaks and turning my head, mostly all the things needed to take care of my mind and my body,'' Thomas said. ''I text Troy every other day. He keeps my mind right mentally and physically.''
Thomas has yet to make his mark for the Steelers thanks in large part to the fact that he's struggled to stay healthy - he plays an overtly physical game and his smaller stature means he often causes as much harm to himself as to the opposition.
Still, despite his injury-prone nature and lack of NFL production to this point, he and Allen seem to be the top two options for defensive coordinator Keith Butler and head coach Mike Tomlin.
Thomas believes that his work with Pittsburgh fan favorite Polamalu this offseason will aid him in his efforts to, not replace, but fill the spot left by Polamalu.
''I definitely am closer to him than I am to anybody,'' Thomas said. ''My second year, I went to him in the offseason and said that I want to be great, and he just told me that being great isn't just about being a great football player. It's putting God first and your family, and everything else will fall into place.''
