Marcus Thuram kneels after scoring a goal. AFP
Thuram's gesture echoed past protests by National Football League players in the US in support of the Black Lives Matter movement.
The issue has surged back into the headlines following the death of George Floyd in Minneapolis.
Thuram's gesture was the second protest in the Bundesliga this weekend.
The 22-year-old French striker continued his recent hot form with two goals as Borussia Moenchengladbach beat visiting Union Berlin 4-1.
Because of social distancing rules, goal celebrations were muted but after Thuram headed his team's second goal just before half time he took the opportunity to make a solitary statement, kneeling and bowing his head.
At half time, his club tweeted a photo with the caption: "No explanation needed." After the game, Gladbach coach Marco Rose said Thuram had his backing.
"Marcus has made the point. He has set an example against racism that we all support," Rose said.
Thuram, whose father, French World Cup winner Lilian runs the Education against Racism foundation in Paris, was the latest show of solidarity with the current protests sweeping the United States.
Naomi Osaka and Serena Williams after the match. File
In the Bundesliga on Saturday, Schalke's US midfielder Weston McKennie wore an armband against Werder Bremen bearing the words "Justice for George".
"To be able to use my platform to bring attention to a problem that has been going on to long feels good!!!" he tweeted.
On Saturday, in the United States, NFL Commissioner Roger Goodell said there "remains an urgent need for action" as violent protests rocked the country.
"The protesters' reactions to these incidents reflect the pain, anger and frustration that so many of us feel," Goodell said. "As current events dramatically underscore, there remains much more to do as a country and as a league."
Serena Williams tweeted a video by Nike, which also sponsors Kaepernick, picking out the line: "Don't pretend there's not a problem in America."
Coco Gauff reacts during a tennis match. File
Two-time Grand Slam tennis champion Naomi Osaka posted pictures of protests from Minneapolis on her Instagram account.
"Just because it isn't happening to you doesn't mean it isn't happening at all," wrote Osaka, whose mother is Japanese and whose father is Haitian.
"To be able to use my platform to bring attention to a problem that has been going on too long feels good!!!" the 22-year-old tweeted.
On Instagram, rising US tennis star Coco Gauff, a 16-year-old African American, showed the faces of black Americans who died in recent years at the hands of authorities or white fellow citizens.
Video footage emerged showing, George Floyd, 46, groaning "please, I can't breathe" and "don't kill me" as a white policeman kneels on his neck.
George Floyd's death sparked nationwide protests demanding a reckoning with institutional racism that have sometimes resulted in clashes with police, but many officers took a less aggressive stance over the weekend when demonstrations were overwhelmingly peaceful.
Chanting "No justice! No peace!" and waving placards with the words "How many more?” at Trafalgar Square, the protesters ignored UK government rules banning crowds because of the pandemic.
Riding on stupendous innings by Wriddhiman Saha, David Warner and an incredible bowling performance by Rashid Khan (3-7) Sunrisers Hyderabad (SRH) trounced Delhi Capitals (DC) by 88 runs in their Indian Premier League (IPL)
Serbian World No.1 Novak Djokovic secured a 7-6, 6-3 victory over compatriot Filip Krajinovic in the first round of the Erste Bank Open in Vienna, Austria, on Tuesday. With the first set going into a tie-break after each player
Virtual confirmation of a play-off berth will be at stake when a depleted Mumbai Indians (MI) take on a rampant Royal Challengers Bangalore (RCB) in a blockbuster top-of-the-table Indian Premier League (IPL) clash on Wednesday.
Cricket South Africa (CSA) announced on Tuesday it will send a security assessment delegation to Pakistan this weekend with a view to the playing in the country in early 2021. If the tour goes ahead it will be South Africa’s first visit to Pakistan since 2007/08.