Mayfield (knee/biceps) was spotted practicing during the portion of Thursday's session that was open to the media, Greg Auman of Fox Sports reports.
Mayfield sat out Wednesday's walk-through session due to knee and right biceps injuries, though his absence may have been more of a maintenance day than anything. His presence on the field Thursday is a good sign that Mayfield will be available to play this weekend in Seattle, though it won't be known until after practice concludes whether the quarterback was a limited or full participant. Assuming he's ultimately cleared in advance of Sunday's contest, Mayfield will be working behind a beat-up offensive line and could be without two key players in running back Bucky Irving (foot/shoulder) and wideout Mike Evans (hamstring), neither of whom has been able to practice so far this week.