The Seahawks fear that Richman suffered a serious knee injury during Sunday's 19-16 preseason loss to the Titans, Mookie Alexander of SB Nation reports.
Richman's knee appeared to buckle during the Seahawks' opening offensive drive. He was able to walk off the field under his own power, but further tests have revealed a long-term injury that will likely lead to the second-year pro opening the regular season on injured reserve.