DENVER (CBS4) – Broncos linebacker Brandon Marshall kneeled during the National Anthem at the start of Thursday night’s season opener.

Andra Day sang the anthem at Sports Authority Field at Mile High, and the television broadcast showed Marshall on one knee as other Broncos teammates were standing.

All of the players on the Carolina Panthers appeared to be standing as well.

LB Brandon Marshall took a knee during the national anthem. Marshall & Colin Kaepernick were teammates at Nevada. pic.twitter.com/QruIeCGBdu — SportsCenter (@SportsCenter) September 9, 2016

San Francisco 49ers quarterback Colin Kaepernick’s decision not to stand for the national anthem during the preseason has sent shockwaves through the NFL, and some players have followed suit. Kaepernick said he is doing it as a protest against the way African-Americans and other minorities are treated in American society.

Marshall talked about his decision to kneel in the locker room after the game.

“I’m not against the military, I’m not against the police or America. I’m just against social injustice,” Marshall said.

Marshall said he will continue to refuse to stand during the anthem at the start of games. He said he also plans to donate an “undisclosed amount” of money to charities that help veterans.

“I’m going to be active in this,” Marshall said.

The Denver Broncos released a statement about the matter to NBC, the network broadcasting the game:

While we encourage members of our organization to stand during the national anthem, we understand and respect it being a personal decision.

Marshall was a teammate of Kaepernick’s when he played college football at Nevada, and he said their personal relationship played a factor in his action.

“Colin is my fraternity brother, my ex-teammate, and I believe in what he’s trying to do. I believe in his actions. So I definitely want to stand by him,” Marshall said.

Marshall left the game midway through the second quarter with an injury. He was taken to the locker room and was evaluated for a concussion, but was cleared to return. The Broncos wound up winning the game 21-20 after a last second missed field goal by the Panthers, but all anyone wanted to ask Marshall about in the locker room afterwards was the statement he made before the game started.

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Eric Reid, Kaepernick’s 49ers teammate, and Seattle Seahawks cornerback Jeremy Lane also chose not to stand during the anthem during preseason games after Kaepernick first did so. A few other NFL players have stated they plan to stage similar protests at upcoming games.

“I feel like this is the right platform. This is our only platform to really be heard. And I feel a lot of times people want us to just shut up and entertain them, shut up and play football. But we have voices as well,” Marshall said. “We’re actually educated individuals that went to college. So when we have an opinion and we speak it, I feel a lot of people bash us for what we have to say.”

Broncos coach Gary Kubiak didn’t take sides when asked after the game about Marshall’s decision.

“I’ll just say this: Brandon is a great kid. He is a leader of this team. I believe in our players, you guys can talk to me about that. I believe in our guys and I believe in them whole-heartedly,” Kubiak said.

The San Francisco 49ers announced on Thursday they are donating $1 million to a pair of Bay Area groups in an effort to improve relationships between law enforcement and local communities.