Colin Kaepernick has called the NFL’s support for anti-racism protests at the start of the season “propaganda” and claimed it is “blackballing” his ex-San Francisco 49ers team-mate Eric Reid.
Kaepernick and Reid began kneeling for the national anthem before matches in 2016 in protest over racial injustice.
Kaepernick has been a free agent since 2017, while Reid is also unattached after leaving the Carolina Panthers.
BBC Sport has approached the NFL for comment.
“While the NFL runs propaganda about how they care about black life, they are still actively blackballing Eric Reid for fighting for the black community,” Kaepernick posted on social media on Sunday.
“Eric set two franchise records last year and is one of the best defensive players in the league.”
Reid is a free agent after parting ways with the Panthers in March, where he had played for the past two seasons.
The 28-year-old was a vocal supporter of the anti-racism movement throughout his time in Carolina, and set Panthers defensive records last year with 130 tackles and four sacks.
Quarterback Kaepernick, 32, has not been picked by a team since 2016 but he has previously said he is “still ready” to play in the NFL, despite his long absence.
In October 2017, Kaepernick filed a grievance against NFL owners because he believed teams were conspiring to not hire him because of his protests.
That grievance came to a settlement in February 2019, alongside a similar collusion case filed on behalf of Reid.
The NFL has changed its position on protests during Kaepernick’s absence. In May 2018, the league introduced a rule which meant teams would be fined if players kneeled during the national anthem.
However, it made a U-turn in June this year, saying protest during the national anthem would be allowed.
This season end zones across the league will bear the words “End Racism” and “It Takes All Of Us”, while players will be allowed to wear helmet stickers featuring the names of victims of racism.
Months of protests have taken place across the United States following the death of George Floyd after he was arrested by police in Minneapolis in May, and the demonstrations continued during the opening weekend of the NFL.
Fewer than a quarter of the stadium’s seats were in use because of Covid-19 restrictions in the first fixture since the outbreak of the virus during the Kansas City Chiefs’ win over the Houston Texans on Thursday.
However, pockets of the crowd booed as players linked arms in a ‘moment of unity’ shortly before the game started.
The only team to allow any fans on Sunday were the Jacksonville Jaguars, who like several teams remained in the locker room during the singing of the national anthem and Lift Every Voice And Sing, considered the black national anthem.
Their opponents, the Indianapolis Colts, were on the sidelines and head coach Frank Reich stepped forward to kneel during the national anthem as players linked arms behind him.
The Jaguars’ decision was taken to avoid a repeat of Thursday’s opener.
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