Detroit Lions cornerback Rashean Mathis was finally diagnosed with a concussion, but it took more than a week before it was officially diagnosed, according to ESPN's Michael Rothstein. After being placed on injured reserve for the third time in his career, the Lions cornerback is thinking about retiring, according to Dave Birkett of the Detroit Free Press.

"It makes me consider my future," said Mathis, via the Detroit Free Press. "Before I even stepped on the field this year, I considered it. So when something like this happens, yeah. As a professional, I'd be naïve to not think about those types of things. Like I said, there's life after football, and you have to think about those things."

Mathis, 35, traveled with the team to London after suffering a concussion against the Minnesota Vikings in week seven and was eventually held out after feeling ill with light headaches. It wasn't until after a week that Mathis was officially diagnosed, but he is reportedly symptom-free now and has not suffered any memory loss, according to Birkett.

The NFL's handling of concussions has been a major topic throughout the league, and with a recent study that showed 87 out of 91 former football players testing positive for brain disease, many players are considering their future health. This past offseason San Francisco 49ers linebacker Chris Borland, 24, retired from football over concerns about long-term effects of repetitive head trauma. With more facts and studies behind this research, players are thinking about their future, and their future health.

"I don't think it would have looked well for the organization, or my part, me being as a man, for me to go back out there and then something bad, worse, happened. And then the organization and my family would have to answer questions about that," said Mathis, via the Detroit Free Press. "(If) I'm not experiencing any symptoms now or in the future, great. We made the right call. And I could have, technically, still played. But if I would have went out there and something worse happened and it was like, 'Oh, wow, what have they done?' So that's how you have to think about it, and me, as a professional, that's how I think about it, as well."

The Lions cornerback signed a two-year contract worth $3.5 million prior to this season and will likely need to decide this offseason whether he will retire.