An undrafted free agent out of Washington State, Abdullah said it was time for him to focus on his "personal health."
"There are numerous deciding factors in my decision, with personal health being foremost,” Abdullah wrote in an Instagram post. “Sitting for five weeks last year after suffering the fifth concussion of my career, I had a lot to contemplate. My goals moving forward are to be of benefit to my family, my community, my country and hopefully the world. Having a sound mind will be vital in accomplishing these goals."
Abdullah suffered a concussion on Nov. 29 last year and missed the final five games of the regular season. He returned to practice on Dec. 31 and played in Kansas City's two postseason games.
Abdullah was signed by Minnesota in 2008 and spent four seasons with the Vikings before joining Kansas City after a one-year hiatus from the league (see related story below). Older brother Hamza Abdullah also played in the NFL from 2005-11 after being drafted in the seventh round.
Abdullah thanked the Vikings for taking a chance on an undrafted free agent and called his three seasons with the Chiefs "the most enjoyable football experience in my entire life."
He returned two interceptions for touchdowns in his NFL career, including one in 2014 against the New England Patriots that led to a 15-yard penalty when he went down to a knee in prayer. The NFL later announced the penalty should not have been called.
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