A statement issued by the team didn't mention why the trade was off, but ESPN reported the trade -- which was to have sent Detroit's Jerome Harrison and a 2013 draft pick to the Eagles -- was called off due to health issues surrounding Harrison.
Asked for his reaction by the Detroit Free Press, Brown answered in a text message, "Lost for words."
Detroit had hoped Brown could add depth to its running corps after leading rusher Jahvid Best was diagnosed with his second concussion of the season.
Brown had been expected to be in Detroit for a physical Wednesday, the newspaper said.
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