Roy Helu is ensured of a spot on the season-opening roster, according to Kyle Shanahan (John McDonnell/The Washington Post)

Roy Helu has secured a spot on the Washington Redskins’ season-opening roster as a backup tailback behind starter Alfred Morris, according to offensive coordinator Kyle Shanahan.

Shanahan said Tuesday that the team’s other roster spots for reserve running backs remain “up for grabs” entering Thursday’s preseason finale at Tampa.

“The only thing that’s been settled is Alf and Helu,” Shanahan said. “Everything else is up for grabs. We’ve got a good problem to have because I think there’s a bunch of guys there that can play in this league and that can help us. They’re gonna make us have to make a tough decision next week. And really, every play is gonna count for them.”

That would seem to mean that Keiland Williams, Evan Royster and rookie Chris Thompson are competing for either one or two roster spots. Thompson potentially could make the team as its punt returner.

The Redskins appear likely to keep only one fullback, Darrel Young. Shanahan said that reserve tight end Niles Paul could line up at fullback when needed.