The news was first reported by the Charlotte Observer.
Since helping Carolina to the Super Bowl during his rookie season in 2003, Gross started all 167 games in which he played. He only missed nine games total during his career and only one in the past four years.
Though he would have been 34 years old before the 2014 season began, he was ranked by Pro Football Focus as the No. 3 tackle in the league in 2013. Carolina just restructured the deals of three players, but losing Gross will be problematic -- and not just for salary cap needs.
Since the Panthers already have plenty of roster holes, the loss of one of the league's premier tackles will cause a headache. The team might have to get active in free agency or modify its draft strategy in order to compensate for Gross' loss. Right tackle Byron Bell could move to the left side, but he also didn't play particularly well last season.
Still, Gross seems content with his decision.
"I've been to a Super Bowl," Gross recently told the Observer. "I've been in the Pro Bowl. I've won the division. I've been 2-14. I've been carted off the field. I've been celebrated off the field. I've had almost everything happen to me that can happen, short of winning the Super Bowl. I feel like I'm a very content person."
And all that success came despite one particular physical trait, according to former teammate Geoff Schwartz.
Congrats @J2theGross on a great career! Luckily those giant ears didn't hold you back from success.— Geoff Schwartz (@geoffschwartz) February 25, 2014