A cheerleader for the San Francisco 49ers appeared to kneel during the US national anthem at an NFL game on Thursday, echoing recent player protests.
The woman, who has not been identified, was pictured kneeling before the team's game against the Oakland Raiders.
The 49ers are the former team of Colin Kaepernick, who knelt during the anthem as a protest back in 2016.
His aim was to highlight police brutality against African-Americans.
While the rest of the cheerleading squad held pom-poms aloft in unison during the Star-Spangled Banner, one woman knelt down and put her hands on her hips.
If confirmed, it would be the first time an NFL cheerleader has protested in this way, although five members of a college team in Georgia did so last year.
NFL protests began in 2016, when Kaepernick - then the 49ers' quarterback - refused to stand for the anthem.
Similar demonstrations spread to other teams, with some choosing to link arms in solidarity rather than kneel.
But the action proved controversial, drawing criticism from fans and from US President Donald Trump.
He has called players who "disrespect" the US flag "sons of bitches" and called for them to be sacked.
Kaepernick opted out of his contract with the San Francisco 49ers in March 2017 and is now suing the National Football League, arguing that team owners deliberately froze him out because of his activism.
In May, the American football league said NFL teams will be fined if their players kneel during the anthem.
Those who do not wish to stand can stay in the locker room until the Star-Spangled Banner is over, the league said.
President Trump welcomed the move, saying players who do not stand "maybe... shouldn't be in the country".
A number of former cheerleaders told ELLE magazine in an October 2017 article that they would never have taken part in the demonstrations.
"If I was still a cheerleader, I wouldn't kneel down, it's not my job," one told the magazine. "I would be frustrated about what's going on in the country, but I would put my thoughts and opinions to the side and keep on moving."