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Videos of Nike shoes being burned are doing the rounds on social media and the company's stock price is dropping after the sportswear giant unveiled a new ad campaign featuring the controversial former NFL player Colin Kaepernick.

The quarterback became a household name after kicking off a debate over NFL players taking a knee during the national anthem to protest racial injustice. This drew the ire of some owners and fans, as well as repeated attacks by President Donald Trump.

"The NFL players are at it again," Trump tweeted on August 10. "Stand proudly for your National Anthem or be Suspended Without Pay."

The new ad campaign, which comes just days before the start of the new NFL season, features a close-up black-and-white shot of Kaerpernick, along with the words, "Believe in something, even if it means sacrificing everything."

For the controversy-averse NFL, the provocative ad campaign is likely an unwelcome PR problem that sows further division among football fans about the issue. The league is currently negotiating with players about how to address its ban on kneeling during the national anthem this season, which starts on Thursday. The NFL issued a ruling in May that said players should stay in the changing room rather than come on the field and kneel in protest. Teams will be fined for infractions, though the NFL has said it is willing to further discuss the issue.

Kaepernick started protesting in August 2016 when he played for the San Francisco 49ers. He said at the time, "I am not going to stand up to show pride in a flag for a country that oppresses black people and people of color. To me, this is bigger than football and it would be selfish on my part to look the other way."

Some fans disagreed with his actions, igniting a national debate about whether kneeling is disrespectful to those who have fought for the country.

In March 2017, Kaepernick opted out of his contract with the 49ers and has since remained without any team affiliation.

His surprise appearance in the new campaign by Nike — which supplies all the jerseys for the NFL — lit up social media.

The frontman for a country music act that performed at Trump's inauguration posted images he claimed were the band's sound man cutting Nike's iconic "swoosh" off a pair of socks. Other images and videos from accounts whose origins couldn't immediately be verified also showed Nike footwear being incinerated, fueling calls for a boycott.

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By flying in the face of controversy just days before the NFL season starts, Nike appears to be living out its slogan, "Just do it."

But in many ways, the new marketing initiative is just par for the course for the edgy sportswear company that has been weighing in on the progressive side of social and cultural issues for the past 30 years.

"Nike never does anything in a vacuum; almost like Apple, they have a reputation for taking a disruptive path," Joe Favorito, adjunct professor at Columbia University, and former head of PR for the New York Knicks, told NBC News.

The company supported Muhammad Ali after his career was over and helped usher back in Tiger Woods' redemption following his DUI arrest. It also introduced an athletic hijab, which provoked both praise and backlash.

"As a company, you are what you stand for," said Mike Jackson, a marketing communications professional. "Long term brand equity is what they're after."

More companies have been wading into social issues during sports broadcasting as events have become more of a family-oriented activity and consumers have shown a willingness to express their political views through their purchasing — especially younger buyers.

Cheerios used a mixed race couple during their 2013 Super Bowl ad, and a same-sex couple and their adopted daughter during the 2014 Super Bowl. The ads prompted racist and homophobic backlash, but also acclaim.

Puma appointed hip-hop megastar Jay-Z, who has spoken out vocally against Trump, as creative director of its basketball division.

Nike said its campaign is designed to appeal to a young audience.

“We believe Colin is one of the most inspirational athletes of this generation, who has leveraged the power of sport to help move the world forward,” Gino Fisanotti, Nike's vice president, told ESPN.

Nike has not confirmed details of the ad purchase, so it remains unknown yet which mainstream audiences beyond those than read about it on social media and in news coverage will see it.