Forbath injured his groin in practice this week, and it worsened.
The Redskins likely will wait to see how Forbath kicks Sunday morning before deciding who will handle that chore. Coach Mike Shanahan said Friday that he did not want to keep two kickers active for the game.
Potter has never attempted a field goal in the NFL and served as a kickoff specialist for Buffalo last season. The Redskins cut him in training camp.
Forbath made 17 of 18 field goals last season but missed his only attempt last Monday in the opener against the Philadelphia Eagles.
White, who had not played in the NFL in three years, was a surprise roster pick coming out of camp, especially with the Redskins having kept three other quarterbacks. But Washington liked how White improved during camp in the zone-read option game.
The Redskins could re-sign White on Monday if he clears waivers. But White might not last a lot longer anyway, as the Redskins will need to release two players when defensive lineman Jarvis Jenkins and linebacker Rob Jackson return after serving four-game suspensions handed down by the NFL.