Marshall wore the green cleats in the game against the New York Giants to promote Mental Health Awareness Week, and said prior to the game he intended to match the National Football League's fine with an equal contribution to a charity involved with mental illnesses associated with breast cancer diagnoses.
The NFL annually promotes breast cancer awareness at its October games.
"The fine is nothing compared to the conversation started and awareness raised," Marshall said on his Twitter account.
His message included a photo of the letter the NFL sent, informing him of the fine, the Chicago Tribune reported Thursday.
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