Harrison, 34, has been a pass-rushing terror in coordinator Dick LeBeau's defense for years, but his dwindling durability and increasing age don't line up with the $6.57 million he's set to make next season.
Harrison will count $10 million against the salary cap in 2013, La Canfora reported, and the Steelers already have handed large extensions to linebackers LaMarr Woodley and Lawrence Timmons. Pittsburgh isn't interested in sinking a fortune into one position, so Harrison might be the odd man out.
Harrison first joined the Steelers in 2002 and became a full-time starter in 2007. The two-time All-Pro registered double-digit sacks three seasons in a row between 2008 and 2010, but he has been slowed by injuries over the past two seasons.
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