ANDERSON Ind. -- It was about this time last year that Robert Mathis was relegated to the "dungeon field," where injured players work out away from their teammates during training camp practices. The linebacker was frustrated and impatient at times; he wanted to be on the practice field with the rest of his team.

The hope was that Mathis would be able to rebound from a torn Achilles and 10 surgeries that cost him the entire 2014 season.

Just as he's done going back to high school, Mathis used those who doubted his playing ability as a motivating factor during his rehabilitation.

"It's plain and simple," he said. "I think I kind of overdo it when people say I can't. That kind of boils my blood a little bit. It drives me to go a little harder."

Mathis' motivation and determination paid off. He got rolling as the season progressed and ended up tying for the team lead in sacks with 7.0 last season to bring his career total up to 118.

"In my opinion, he is a future Hall of Famer," Colts linebacker D'Qwell Jackson said. "With the amount of sacks he's generated, from where he started from a small school to where he is now, it's remarkable that he still carries a chip on his shoulder. Even last year with limited time, he still had seven sacks and led this team in sacks. With a healthy Robert Mathis, he is still hitting a ceiling that most of us don't have."

Mathis is a staple inside the Colts organization. He's joining Johnny Unitas, Peyton Manning and Reggie Wayne as the only players to play at least 14 seasons with the Colts.

That's not bad company for Mathis.

"I just have to get on the same level as those guys," Mathis said. "That's a lot of Hall of Famers right there. I just have to carry my weight and get a seat at the table."

Mathis, to no surprise, is motivated again this season.

He's heard and read about the questions surrounding the Colts' lack of a pass rush. Mathis will not only be looking to prove that the Colts have a pass rush, he'll be out to show that he can still get to the quarterback at the age of 35.

He's also in a contract year. A big year on the field could land him another contract. If he struggles, well, Mathis knows how the business goes. He's watched as the Colts have unceremoniously parted with ways with the likes of Manning, Wayne and Jeff Saturday over the past four years.

"It's strictly about getting the job done," Mathis said. "If you don't do it, then you're out the door. If you do do it, then there's a chance. It's a business. I don't care how you slice the pie. Business is the first ingredient. Let's keep this real."