What the president said
Speaking at a campaign rally in Alabama Friday night the president said: "Wouldn't you love to see one of these NFL owners, when somebody disrespects our flag, to say: 'Get that son of a bitch off the field right now, out."
On Sunday, before NFL games kicked off, the president's tweets reinforced his anti-anthem protest message.
...NFL attendance and ratings are WAY DOWN. Boring games yes, but many stay away because they love our country. League should back U.S.— Donald J. Trump (@realDonaldTrump) September 24, 2017
He also suggested that if fans refuse to go to games due to the protests, "you will see change fast."
Appearing to be responding to critics who say his slam of players who kneel in protest is about race, the president said Monday that his criticism of players who kneel during the national anthem "has nothing to do with race."
How the NFL responded
Saturday the NFL Commissioner Roger Goodell released a statement saying "Divisive comments like these demonstrate an unfortunate lack of respect for the NFL, our great game and all of our players, and a failure to understand the overwhelming force for good our clubs and players represent in our communities."
The president of the NFL Players Union, which represents current and former players, released a statement on Saturday: "The balance between the rights of every citizen in our great country gets crossed when someone is told to just 'shut up and play.'"
What happened on Sunday?
On Sunday, around 100 players took a knee across the league and the Pittsburgh Steelers, Seattle Seahawks and Tennessee Titans did not take the field for the national anthem. Also not taking the field, the New Orleans Saints who played the Carolina Panthers. Julius Peppers remained in the locker room, saying to Panthers.com:
"I want to get one thing clear: This wasn't about disrespecting the military, disrespecting the police, first responders - none of that," Peppers said. "It was about me making a decision as a man on my two feet. I didn't want to ask anybody else to do anything with me. I thought it was appropriate to stay in. We know what went on this week; the comments that were made by the President. I felt like he attacked our brothers - my brothers in the league. I felt it was appropriate to stand up with them and stay in the locker room."
Statement from Panthers Owner/Founder Jerry Richardson pic.twitter.com/aTDcTkfIRW— Carolina Panthers (@Panthers) September 25, 2017
How are other sports reacting?
The Oakland A's Bruce Maxwell became the first MLB player to kneel for anthem on Saturday. Coming from a military family, Maxwell placed his hand on his heart while taking a knee before the game. Fellow teammate Mark Canha put his hand on Maxwell's shoulder during the national anthem.
Meanwhile, NASCAR owners are weighing with several saying that they would fire anyone who didn't stand for the national anthem. NASCAR released the following statement on Monday:
NEW: NASCAR releases statement affirming "respect for the national anthem" and the "right to peaceably express one's opinions." pic.twitter.com/2PFbnrE7u5— ABC News (@ABC) September 25, 2017
NASCAR driver Dale Earnhardt Jr. said Monday he supported the NFL players and owners who protested on Sunday in response to President Donald Trump's criticism of players who kneel during the national anthem.
All Americans R granted rights 2 peaceful protests— Dale Earnhardt Jr. (@DaleJr) September 25, 2017
Those who make peaceful revolution impossible will make violent revolution inevitable-JFK
The president rescinded an invite to Stephen Curry to visit the White House, which is a tradition for NBA champions.
"Going to the White House is considered a great honor for a championship team. Stephen Curry is hesitating, therefore invitation is withdrawn!" Trump tweeted while spending the weekend at his golf club in New Jersey.
The Warriors had a response to Trump's tweet. In a statement, the team said, "There is nothing more American than our citizens having the right to express themselves freely."
LeBron James, perhaps one of the most recognizable athletes in the world, also tweeted his disagreement with Trump.
"U bum @StephenCurry30 already said he ain't going! So, therefore, ain't no invite. Going to the White House was a great honor until you showed up!" James said.
U bum @StephenCurry30 already said he ain't going! So therefore ain't no invite. Going to White House was a great honor until you showed up!— LeBron James (@KingJames) September 23, 2017
At a Monday press conference James added:
"It's powerful what all these athletes are doing," James said. "It's not about the disrespect of our flag and the military that's made this world free."
"It's about equality."
UNC's national championship team also announced that it will not be visiting the White House, citing a scheduling conflict. It's unclear if the move is related to the president's recent comments.
World War II vet defends players
A 97-year-old World War II veteran insisted that "those kids have every right to protest" as he joined the "take a knee" protest over the weekend, and now the photo posted by his grandson is going viral.
The grandfather, John Middlemas of Missouri, told the News-Leader that he did it to spread a message of love.
"I'm trying to say that you have to love everybody," he said, adding that he wants to teach what he always teaches his grandkids: "Be like Jesus."
South Carolina restaurant bans NFL games
A South Carolina restaurant owner says he won't be showing any NFL games in his business until the national anthem protests end.
David McCraw, owner of Palmetto Restaurant and Ale House in Greenville, announced his decision on the restaurant's Facebook page.
How will history judge?
We don't have any polling specifically about Trump's recent NFL comments, but a Quinnipiac University poll from 2016 found that only 38 percent of those surveyed approved of players choosing not to stand during the anthem. But while these NFL protests may be unpopular right now, similar protests in the past - involving race, civil rights and varying definitions of patriotism - came to be viewed much more positively after the fact.
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ABC News and the Associated Press contributed to this report