CHARLOTTE, N.C. -- Carolina Panthers quarterback Cam Newton says it's "unfair" that former San Francisco 49ers quarterback Colin Kaepernick isn't on a roster.

"I really think it's unfair," the 2015 NFL MVP said on Tuesday as the Panthers prepared for Sunday's opener at San Francisco. "Not to take any [story] or glory away from this game, we're trying to find every way to be prepared for the 49ers come Sunday.

"But, in my opinion, do I think Kaepernick is better than some of these starting quarterbacks in this league? Absolutely."

Kaepernick hasn't been on a roster since opting out of his contract following the 2016 season. Many around the league publicly have said the free-agent quarterback, who led San Francisco to the Super Bowl following the 2012 season and to the NFC Championship the next year, has been blackballed because of his refusal last season to stand for the national anthem.

Newton is the latest high-profile quarterback to say Kaepernick should be on a roster. Green Bay's Aaron Rodgers recently specified the reason Kaepernick isn't on a roster is "because of the protests."

"Should he be on a roster? Absolutely," Newton said. "There's no question about it. Is he good enough to be on a roster? Is he good enough to be a starting quarterback? Absolutely.

"But our main focus right now is on beating the 49ers on Sunday."