Whether you still look at Harrison as a bigger villain than Le'Veon Bell, you have to acknowledge his time in Pittsburgh.
He took to Instagram to make the announcement on Monday morning, posting a collage of photos of his children with the caption "I've missed way too much for way too long.and I'm done. Many thanks to my family, coaches, the fans, and everyone who played a role in my football life", Harrison said.
Harrison finishes his career with 84.5 sacks, 34 forced fumbles and eight interceptions to go along with 795 total tackles.
And what did Harrison do with his newly found free time?
A year ago, the Steel City was rooting for their aging veteran to pound out one more season and hang up the cleats in the locker room he established himself in.
Harrison, who turns 40 next month, retired for the first time in August 2014, only to return to the Pittsburgh Steelers less than a month later after the team's defense suffered a number of injuries.
Harrison quickly signed with the New England Patriots.
He played 90 percent of the team's defensive snaps in Super Bowl LII and was arguably their most effective player on the front seven. The Ravens sent him to NFL Europe before eventually releasing him.