SEATTLE -- Richard Sherman says NFL players don't have a reason to trust the NFL, particularly when it comes to protecting their health.

"It's hard to stress player safety in such a violent game because, at the end of the day, ratings sell. People want to buy tickets. People are going to come to games, regardless," said the outspoken Seahawks cornerback.

Sherman gave his thoughts about how the league treats players regarding injuries during a four-and-a-half minute, black-and-white video on The Player's Tribune. Sherman says he understands injuries are going to happen in football. But although the NFL has been more active in making changes to address player safety, he says profits still weigh heavily in the decision-making.

"You're going to get arthritis in your knees. You're probably going to have some stress in your back. Your ankles are going to crack and pop all the time. It's just things that come with the territory. Decisions and sacrifices you knowingly make coming into this game. But the NFL really could care less," said Sherman.

The NFL has been dogged in recent years by concerns about concussions that leave lingering mental effects for former players. It's led to multiple lawsuits. Hits to the head are strictly forbidden now.

Referees have been known to now throw the yellow flag if it just looks like a player hit another in the head, even though they didn't. A perfect example is when Seahawks safety Kam Chancellor laid a particularly violent hit on 49ers tight end Vernon Davis that knocked him out of the game with a concussion in 2012. Chancellor was flagged for helmet-to-helmet contact, but replay showed the contact was a legal shoulder-to-chest.

At every NFL game, medical staff watch for signs of a concussion. If they see a player who may have had his bell rung, that player is supposed to be pulled from the game for evaluation.

Sherman brings up this in the controversy from the NFL's season opener between the Denver Broncos and Carolina Panthers. Late in the game and down by a point, Panthers quarterback Cam Newton took a hard shot to the head. Some thought he should have come out for fear of a concussion, but the medical staff determined he could stay in.

"... you see this guy on his hands and knees shaking his head after he just took a shot to the face and they say they didn't see any indications that he needed to come out of the game," said Sherman. "If you take the reigning MVP out of a game in the last couple of minutes with the game on the line, he'd be frustrated. The fans would be frustrated. But it would be in line with what you said that you wanted to see in terms of player safety. But you didn't because it would affect the ratings because it would affect the game."

Sherman made it clear he believes the NFL sees players as disposable.

"If you can increase their bottom line, then they'll love you. They'll do everything they can to put you out more, to market you, to make sure the fans buy your jersey," said Sherman. "If you're not making them money then, at the end of the day, they're going to find somebody else.

"We really don't have reason to trust the NFL, and I don't think they mind either way," he added. "They're going to do what they have to do to make their money and make as much money as they can for the owners and our union is going to what they can to protect the interests of the players and the rights of the players and help them make as much money as possible."

Sherman is the Seahawks' representative on the board of the NFL Player's Association. He says he joined to help make the union stronger.

Sherman says he believes most NFL players do not come from an affluent background, so their short professional careers (an average of 3.3 years according to the union) are a chance to change the outlook for them and their families.

"To make sure their kids get a better shot at an education. Maybe they're paying for their kids' college. Buying their parents house or buying their siblings a house or getting people in a better situation than they were in before," said Sherman.