The 28-year-old Merling appeared in three regular-season games for Washington, recording two tackles. Merling has previously played for Miami (2008-2011) and Green Bay (2012).
Potter, a second-pro from Western Michigan, hit 3-of-4 field goals in three games in place of Kai Forbath, who missed time with a groin injury. The 23-year-old Potter also forced touchbacks on 8-of-14 kickoffs.
Washington has its bye in Week Five. It next plays on Sunday, Oct. 13 at Dallas.
UPDATE 1:03 p.m. ET: Washington gets roster exemptions of one week for Jackson and Jenkins, according to Mark Maske of the Washington Post. This means they have two extra spots for that period of time.