Harrison had been mulling retirement, but had planned to make an announcement on his future in advance of the start of free agency on March 10.
The longtime Steeler had previously retired after a rocky year with the division rival Bengals and some flirtation with the Cardinals last offseason. Of course, he was coaxed out of retirement early in the season after the Steelers dealt with a number of injuries to their young linebacking group.
Last year, Harrison gave special consideration to the Steelers because of his history there and familiarity with the scheme. It is unclear if he would have come out of retirement to play with another team on such short notice.
As for this season, Kaboly writes that Harrison would prefer to come back with the Steelers. That would depend on what the Steelers want, with Lawrence Timmons, Jarvis Jones, and Ryan Shazier expected to make up three out of the four spots in the starting rotation for linebackers. If Jason Worilds leaves in free agency, Harrison could be a cheap alternative to provide a pass rush.