Sterling K. Brown has taken to Instagram to share some touching words about Chadwick Boseman.

Boseman died Friday of cancer, his representative said. He was 43.

The actors starred alongside each other in “Marshall” and “Black Panther”.

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“If still waters run deep then Chadwick Boseman was a deep brother,” says Brown in the clip.

“Little did I know the whole time that I knew him that he was living with cancer,” he continues.

Brown describes Boseman as “quiet,  private but still cool.”

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“I grieve this loss of another young black man. It’s not racism or police brutality, this one is cancer,” Brown went on.

“Cancer effects my community in a disproportionate way. There’s so much going on right now and you just don’t want to see anyone else die.”

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Finishing the video, Brown added: “He was just a good dude. As goofy as I am, he was equally cool. And he cared. He cared about every line. He cared about every shot. He really, really cared.

“He’ll be missed.”