PITTSBURGH (AP) — Longtime Pittsburgh Steelers linebacker James Harrison, a former Kent State standout, is taking a second crack at retirement.

The five-time Pro Bowler and 2008 NFL Defensive Player of the Year announced on Instagram early Monday that he is stepping away from the game following a 15-year career.

Harrison, who turns 40 next month, posted a collage of pictures of his two sons and noted he’s “missed way too much for way too long ... and I’m done.”

Harrison played nearly his entire career with the Steelers and the 84.5 sacks he collected while wearing black-and-gold are a franchise record. He spent the 2013 season in Cincinnati and signed with New England late last season, appearing in all three playoff games for the Patriots, including their Super Bowl loss to Philadelphia.

This is the second time Harrison has called it quits. He retired briefly in September 2014 only to be lured back to the Steelers. He remained productive into his late 30s, registering at least five sacks from 2014-16.

Harrison officially joined the Golden Flashes program in 1999, a year after he graduated from Coventry High School. He was named First Team All-Mid-American Conference as a senior in 2001 after compiling 98 tackles, 20 tackles for loss and 15 sacks as a rush linebacker under head coach Dean Pees.

Harrison went undrafted, and was signed as a free agent by the Steelers in 2002. He was on and off PIttsburgh's practice squad during the next two years, then spent some time with the Baltimore Ravens. After the Ravens cut him, Harrison was signed once again by the Steelers in 2004 — and this time he took full advantage of the opportunity.

After making his mark mostly on special teams in 2005 and 2006, Harrison became an All-Pro linebacker in 2007 and remained one of the most feared defenders in the NFL for the next several years.

Kent State named its fieldhouse weight room the James Harrison Strength and Conditioning Center after Harrison made a $100,000 donation to the football program in 2012.