The refusal of San Francisco 49ers quarterback Colin Kaepernick to stand for the American anthem has unleashed a wave of controversy and debate.
At the weekend, while a naval officer sang the first notes of The Star-Spangled Banner and dozens of military personnel unfurled an oversized flag on the football field, Colin Kaepernick dropped to one knee on the 49ers' sideline.
With his silent gestures of protest, Kaepernick intends to keep drawing attention to a litany of American problems.
The move inevitably drew criticism but it is also garnering considerable support, including from US president Barack Obama.
“[He's following his constitutional right to make a statement,” Obama said yesterday in response to a question about the player. “I think there’s a long history of sports figures doing so.”
“I don’t doubt his sincerity. I think he cares about some real, legitimate issues that have to be talked about.
"I'm not anti-American. I love America," said Kaepernick, who stayed on the field long after the game to sign autographs for enthusiastic fans. "I love people. That's why I'm doing this. I want to help make America better, and I think having these conversations helps everybody have a better understanding of where everybody is coming from."
Kaepernick's protest has dominated public discussion of the nation's most popular sport this week, and his stance has been met with passionate condemnation and support. His refusal to stand for the anthem first came to public notice last week when he remained seated on the 49ers' bench before a preseason game against Green Bay.
The quarterback cited numerous reasons for his actions, ranging from racial injustice and minority oppression to police brutality and the treatment of military veterans.
Kaepernick said he plans to continue his protests during the regular season. He also intends to donate one million dollars "to different organisations to help these communities and help these people", declining to provide details.
"The message is that we have a lot of issues in this country that we need to deal with," he said. "We have a lot of people that are oppressed. We have a lot of people that aren't treated equally, that aren't given equal opportunities. Police brutality is a huge thing that needs to be addressed. There are a lot of issues that need to be talked about."
When Kaepernick left the field following pre-game warm-ups, he was greeted with profanity and obscene gestures from Leo Uzcategui, a 20-year Navy veteran in a military-green Chargers jersey with quarterback Philip Rivers' No 17 in camouflage numbering.
"I was in the Navy and I saw men and women bleed and die for this flag," Uzcategui said. "If he wants to do something, go to some outreach programme where he can do some good.”
A sign in the crowd read: "You're an American. Act like one."
But Domenique Banks, a 23-year-old fan from nearby Oceanside, California, got the quarterback to sign his Kaepernick jersey before the game.
"I told him I appreciate what he is standing up for," Banks said. "He said he appreciated it. Most of the people I talk to say the same thing. I don't like that he is sitting during the national anthem, but I appreciate what he is standing for."
When the same naval officer performed God Bless America before the fourth quarter, Kaepernick remained standing and then applauded along with his team-mates.
Kaepernick does not intend his stance to be a criticism of the military. When the Chargers' public-address announcer asked fans to recognise active military personnel during a timeout, the quarterback stood and enthusiastically applauded along with his team-mates and the entire stadium.
"I realise that men and women of the military go out and sacrifice their lives and put themselves in harm's way for my freedom of speech, and my freedoms in this country, and my freedom to take a seat or take a knee," Kaepernick said. "So I have the utmost respect for them, and I think what I did was taken out of context and spun a different way."
Kaepernick's social activism, which only emerged publicly in recent weeks, also included support for the Black Lives Matter movement through social media.
Don't use my service--or that of any veteran--to justify the silencing of black Americans. Not on my watch. #VeteransForKaepernick— Charlotte Clymer🏳️🌈 (@cmclymer) August 31, 2016
While negative reaction to the quarterback has been strong, Kaepernick also has been widely praised for his commitment to his stance. Veterans and military members tweeted their support for Kaepernick in recent days under the hashtag #VeteransForKaepernick.
Others have shown their support by buying jerseys with Kaepernick's name emblazoned on the back. As of Tuesday morning, the Colin Kaepernick scarlet game jersey was the bestselling item on Nflshop.com.