MLB manager, players kneel for national anthem, sparking Trump criticism of the social justice protests

National anthem kneeling as a form of social justice protest has grown in popularity in Major League Baseball, demonstrated as numerous players and coaches knelt before an exhibition game Monday that wasn't even played in front of any fans, CBS News reported.

What's the story? While the NBA has welcomed social justice protests in various forms, and NFL players have knelt during the anthem for years to protest police brutality against minorities, the protests did not really catch on in Major League Baseball, a sport with a significantly smaller percentage of African American players and coaches.

Tuesday, however, San Francisco Giants manager Gabe Kapler and several of his players took a knee during the anthem to protest recent incidents of police violence against black people.

Kapler explained his decision to kneel:

"I wanted them to know that I wasn't pleased with the way our country has handled police brutality and I told them I wanted to amplify their voices and I wanted to amplify the voice of the Black community and marginalized communities as well," Kapler said. "So I told them that I wanted to use my platform to demonstrate my dissatisfaction with the way we've handled racism in our country. I wanted to demonstrate my dissatisfaction with our clear systemic racism in our country and I wanted them to know that they got to make their own decisions and we would respect and support those decisions. I wanted them to feel safe in speaking up."

Kapler said he doesn't know whether he or other team members will continue to kneel throughout the season, but that they will make those decisions one game at a time.

Trump opposes protests: The next day, President Donald Trump reiterated his stance against the protests.

"Looking forward to live sports, but any time I witness a player kneeling during the National Anthem, a sign of great disrespect for our Country and our Flag, the game is over for me!" Trump tweeted.

Major League Baseball posted a tweet Monday attempting to explain why the protests aren't disrespectful.

"It has never been about the military or the flag," the tweet read. "The players and coaches are using their platforms to peacefully protest."

In another tweet, MLB stated that "supporting human rights is not political."

The 60-game MLB season begins Thursday.