Kirk Cousins throws against the Falcons (John McDonnell/The Washington Post)

Rookie quarterback Robert Griffin III participated in the Washington Redskins’ practice Wednesday, three days after suffering a concussion during a loss to the Atlanta Falcons. Even so, Griffin’s rookie backup, Kirk Cousins, said he will prepare this week as if he’ll be needed to start Sunday’s home game against the Minnesota Vikings in place of Griffin.

“I said in week one what my approach would be and that doesn’t change—prepare as if I’m going to start the game and whether or not I do, feel good about my preparation,” Cousins said Wednesday in the locker room at Redskins Park.

Griffin’s participation in Wednesday’s practice doesn’t ensure that he will play Sunday. He still must be cleared by doctors to absorb contact in practice and a game.

“I’m just taking it as it comes,” Cousins said. “And obviously with Robert’s situation, there’s nothing set in stone, either. He has to continue to pass tests. I don’t think anybody really knows exactly what’s going to happen day by day.”

Cousins made his NFL debut last Sunday, replacing Griffin in the third quarter. Cousins threw a 77-yard touchdown pass to veteran wide receiver Santana Moss. But he also threw two late interceptions to seal the outcome of the Redskins’ 24-17 defeat. He completed five of nine passes for 111 yards.

“I learned a lot,” Cousins said. “More than anything, I learned that I can do it. I learned that I can go in there and I can move the football, be a part of an offense that moves the football. I think I came away from Sunday’s outing obviously with some disappointments but also with confidence and a belief in myself that with the right preparation continuing, I can do it and I can make it in this league.”

The Redskins also have veteran quarterback Rex Grossman on the roster. But Grossman has been on the inactive list for each game this season with Cousins as Griffin’s primary backup.

Cousins has a more conventional playing style than Griffin’s, meaning the Redskins may have to prepare this week to have one offensive approach if Griffin plays Sunday and a different approach if he doesn’t.

“I don’t know if it’s a problem,” Cousins said. “I think that we both have different skill sets. You guys know that. So certainly the plays that are called that are going to put Robert in a good position to be successful are different at times than the plays that will be called that are going to put me in a position to be successful. There are some differences. But at the end of the day, our base offense is still our base offense. To be a quarterback in the NFL, you have to still be able to be accurate, make good decisions, and those are the things that both of us are working on.”