Still, they play an invaluable role in where the ball ends up at the conclusion of each play.
"Something I've noticed being on lots of different teams is that they're always looking for that sixth blocker – five offensive linemen and then it's either an on-the-line tight end like myself or more of a fullback," Hartsock said. "We've got a little bit of all of that here."
All three players are in their first year with the Panthers, and all took different paths to Charlotte. Yet all are capable of playing a crucial role in Carolina's next effort to get its running game going Sunday in Chicago.
Hartsock is by far the veteran of the group, now in his eighth NFL season. He's the consummate blocking tight end, having caught just 29 passes in 90 career games with five different teams. A third-round draft choice of the Indianapolis Colts in 2004, the Ohio State product scored his only career touchdown with the New York Jets in 2009.
Still, he's played a part in some significant numbers, helping various offenses (Colts, Jets, Titans, Falcons) rank in the top five in rushing in each of the past five seasons.
"I've never been a flashy guy, but I've always been dependable," Hartsock said. "A lot of coaches have been able to rely on me, and they know I'm not going to make them look bad as a coach.
"I'm not going to do anything that's going to jump off the screen too much, but rarely do you look bad."
Felton, a fifth-round draft pick by Detroit in 2008 claimed off waivers from the Lions on Aug. 31, put up some eye-popping numbers in college. He scored 67 touchdowns at Furman, including 23 rushing touchdowns as a junior, and he did run the ball 40 times and caught it 30 times in three seasons in Detroit.
So it's not surprising that he's the one member of the trio to touch the ball this season – a 3-yard rush.
"I've had a lot of success in the Carolinas, so this is home to me from a football standpoint," Felton said. "I'm happy to be here, and I feel a good vibe around this team. We have something in the making, and hopefully the potential will be realized this year."
Felton also sees the potential for his role to expand as he gets more comfortable in his new home.
"I think it's still developing," he said. "As I get into the system more and they get more comfortable with me, it might expand.
"Whatever they want to do, I'm up for. Right now, I'm just anxious to block for these backs. I've never been around talent at running back like we've got."
While Felton and Hartsock have each been inactive for one game, Brockel has played in all three. Undrafted out of Boise State in 2010, the San Diego Chargers signed him but then waived him in the final roster cutdown.
The Panthers' new coaching staff, however, had familiarity with Brockel, and they've put a lot of trust in him.
"It's a similar role to what I've had my whole life in football. I've always been kind of a utility guy, playing tight end, playing fullback, playing special teams," Brockel said. "I've always kind of just fit in where the team needs me because I'm in between a lot of things. I'm not really the prototypical tight end – I don't really have that height – and at fullback I don't truly fit there, either.
"The main thing that has always helped me is working hard and having a good attitude. Those are the only things you can really control in your life every day. I think that really stands out on the field in the way I play."
Head coach Ron Rivera said he'd like to have 53 players with Brockel's mentality. For now, he's happy to have two fullbacks with unique skill sets.
"It's a good mix," Rivera said. "Richie is more of a blocker who will get his hands on you who is strong and stout and can really wrestle you. Felton is a good, fast blocker who delivers a blow. He's not going to try to wrestle you; he's going to hit you and drive you. It makes for a good combination."
At the end of the day, Brockel, Felton and Hartsock simply love playing football regardless of whether they touch the football. Brockel proved that again this summer, when he helped the virtually unknown U.S. national team win gold at the World Championship of American Football in Austria.
"It was a good time," Brockel said. "It was crazy. I was really surprised how much they loved football over there. The championship game was packed, and people were going nuts, but you can tell they still don't quite understand some things about the football environment. You would walk up to the line of scrimmage, and they're still blasting music and blowing horns.
"It was cool and interesting."