American football cornerback Marcus Peters raised his fist and several other players knelt during performances of the US national anthem, the latest protests in the National Football League made to draw attention to racial inequality.
The gesture on Sunday by Peters, 23, who is African-American, recalled the raised fist demonstration by black athletes Tommie Smith and John Carlos during their medal ceremony at the 1968 Olympic Games in Mexico City.
San Francisco 49ers backup quarterback Colin Kaepernick started a controversy when he began the protests against injustice and police brutality by refusing to stand for "The Star-Spangled Banner" during pre-season games.
San Francisco 49ers quarterback Colin Kaepernick's protest during the Star Spangled Banner resonates in African-American community as the NFL season starts and other players join [Reuters]
A San Francisco 49ers fan holds up a sign in referring to Kaepernick's protest during the second half of the game against the San Diego Chargers at Qualcomm Stadium [Reuters]
Peters and other members of the Kansas City Chiefs linked arms during the anthem, as did the Seattle Seahawks at their game in Miami, although the exact meaning of their gestures was not immediately clear.
Sunday's games fell on the 15th anniversary of the September 11 attacks on the United States and many National Football League teams commemorated the attack with special ceremonies.
Four Miami Dolphins players - Arian Foster, Jelani Jenkins, Michael Thomas, and Kenny Stills - knelt while the national anthem was played at their season opener against the Seahawks. On the other side of the field, the Seahawks locked arms while standing during the song.
Photos published online by Sports Illustrated magazine showed Tennessee Titans players Jurrell Casey, Wesley Woodyard and Jason McCourty raising their fists ahead of their game against the Minnesota Vikings as well.
Representatives for the teams could not be immediately reached for comment.
Kansas City Chiefs players decided to lock arms as a sign of solidarity after discussing the issue as a group.
"It was our goal to be unified as a team and to be respectful of everyone's opinions, and the remembrance of 9/11," the team said in a statement. "It's our job as professional athletes to make a positive impact on our communities and to be proactive when change is needed."
Seattle wide receiver Doug Baldwin, in a video he posted online announcing his team's decision to link arms, said, "Progress can and will be made only if we stand together."