Denver Broncos linebacker Brandon Marshall has described a vile, racist letter that he received and shared on Instagram as "extremely concerning".
Marshall, who followed Colin Kaepernick's protest by taking a knee during the national anthem, received a hand-written note containing a host of racist insults, in addition to an apparent physical threat that read: "We are 'channeling' a devastating hard hit for you!! Something to make you an invalid in a wheel chair [sic]."
He duly shared the letter on Instagram with a caption that read: "The hatred by some against people of color is one of the reasons we are where we're at in the world today, and they wonder why we feel the way we do and take the stances that we take."
In quotes reported by the Broncos' official website, Marshall added: "It was extremely concerning. To me, it just lets me know that stuff still exists. That's the reason I put it out - to expose what everybody thought was maybe put to bed, put to rest. But that stuff is still alive, and still exists.
"And just so many racist, derogatory terms that were in it. It was a bunch of crazy things that were in it. I'm like, 'Man, this is wild'.
"It takes so much energy to hate. I just don't understand it. Disgusting, disheartening, deplorable - you can use a bunch of words for it."
Marshall received messages of support on Instagram and Twitter after sharing the appalling message.
He added: "I've heard good things like people saying, 'Just because I didn't agree with what you did [kneeling for the national anthem], I still care about you as a human being. I still wouldn't wish any harm or malice towards you'."