Robert Griffin III and the Redskins face the Cowboys Sunday night. (Toni L. Sandys/The Washington Post)

Already in his young NFL career, Robert Griffin III has had quite a few big moments: the season opening win at New Orleans, the comeback victory at Tampa Bay, the game-clinching 76-yard touchdown run versus Minnesota, back-to-back four-touchdown games against Philadelphia and Dallas, the Monday Night Football win over the Giants. But none carries as much weight as this Sunday’s regular season finale against the Cowboys.

With a win, Griffin will help the Redskins capture their first NFC East title since 1999, and their first playoff berth since 2007. With a loss, the Redskins could be done for the year unless Chicago and Minnesota both lose.

 “This is why you coach. This is why you play,” Redskins coach Mike Shanahan said of this week’s game. “These are the games you remember for the rest of your life, because they don’t come around every day.”

Griffin acknowledged the magnitude of this week’s matchup Wednesday, a game that will be nationally televised beginning at 8:20 p.m.  But he said he and his teammates can’t dwell on how much is at stake.

“It is the biggest stage, but none of us are looking at it that way,” Griffin said. “It’s another game we have to go out and win. That’s the way we’re looking at it. Every moment in your life is the biggest one at that time. We look forward to having many more of these, but we’ve got to make sure we take care of this one.”

Griffin may be a rookie, but he’s no stranger to high-pressure situations.

In 2011, he led the Baylor Bears to a 9-3 record and a win in the Alamo Bowl. During that season, Griffin owned the spotlight as the eventual Heisman Trophy winner. As a freshman, he won the Big 12 championship in the 400-meter hurdles and advanced to the semifinals of the Olympic Trials in the same event.

Griffin said those experiences helped him learn the importance of maintaining an even keel in high-pressure games.

“It’s just whatever you’re doing: basketball, the big game; in track, the finals or whatever it is; whenever you play the moment up too big, it can be too big to seize the moment,” Griffin said. “You just want to make sure you don’t make something so big that you can’t grab a hold of it. So that’s why I think a lot of guys aren’t necessarily downplaying the game, but they’re not going to talk the moment up as the most important game of our lives. We just have to go out and win a football game, and that’s what they pay us to do.”

The Redskins have rebounded from a 3-6 start, winning six consecutive games since their bye week. Back then, following a loss to the Carolina Panthers and just before departing for the bye week break, Griffin said that his team was far from done, and predicted that they would turn their season around in the second half.

Now that Washington has done just that, Griffin said that he isn’t surprised and that his bye-week prediction wasn’t just him putting on a good front.

“You want to talk yourself up, but you don’t say something you don’t believe in,” Griffin said. “Going on the break, like I told everybody, I was able to clear my head, and just know that you don’t have to freak out in a situation like that. As long as everyone takes the right mindset into every game the rest of the season, you can win them all. We’ve done that to this point, and we expect to finish it.”