ASHBURN, Va. – The great test of Robert Griffin III will not come on the first cut he makes on his rebuilt right knee. It won't come on Monday night when the Philadelphia Eagles send their first blitz not previously detected on film. The test will come in the cavern of FedEx Field when he takes off running.
What will happen when he has 10 yards and the Redskins need 15 and a tackler is coming? Will he fake? Will he sprint? Will he slide?
There's no way he can continue the way he did last year, when he kept trying to prove he could take a tackle. He can't dance around the giants the way he did with Baltimore's 340-pound tackle Haloti Ngata, who instead fell on top of him, ruining Griffin's knee for the rest of the season. Either he slides or he breaks.
Even Michael Vick, a quarterback beaten up by the blows of defenders in recent years, understands that he must slide. And nobody, not even RG3, has been as stubborn about ducking contact as Vick. It is a choice with a price, one that cost Vick 13 games the last three seasons.
"What I've learned is that you have to be cautious, the guys in this league hit so hard and we only weigh about 200-210 pounds, and these guys take all kinds of angles and we don't see them sometimes," said Vick who weighs 215. "So it's important for us to protect ourselves and be conscious of where we are on the field and, more importantly, understand how much we mean to our football team."
Vick said this is only a recent discovery. It's a lesson he learned this past offseason when he feared for his job being 33 years old with a long injury history and a new coach in charge of the team.
Not that this was easy. In fact it might have been the toughest thing Vick has had to do as a football player. But in this preseason, the Vick who never met a defensive end he didn't think he could twist around or run past, instead fell safely to the ground.
"I think once you tell yourself that's what you're going to do, then you kind of ingrain it in your mind," Vick said.
Of course telling the 217-pound Griffin to avoid the kind of hit that can ruin his career and having him do it are different things. Redskins coach Mike Shanahan lectured RG3 many times last year about the value of sliding or running out of bounds only to have Griffin nod, promise to change and then choose to keep running when ducking would have been smarter.
He laughed on Wednesday when the subject came up. He said he will be thinking about sliding and ducking on Monday night.
"I mean you guys have talked to me about it for eight months," Griffin said, "I think it's ingrained in my mind."
No topic might swirl more around a Redskins team that is deeper and healthier than it has been in many seasons.
"Robert, Robert, Robert, that's all you guys ask about," joked wide receiver Santana Moss. "I have to tune into my Robert channel in my head."
But the message delivered by coaches, fans and journalists is the same one pushed in the locker room he has come to own in barely more than a year as a professional player. With Griffin the Redskins are a Super Bowl contender. Without him they might be the worst team in the NFC East, especially given backup quarterback Kirk Cousins' ankle injury.
[Watch: Who will win Super Bowl XLVIII?]
Which is why running back Alfred Morris – whose 1,613 rushing yards last year came on a large part because of RG3's ability to run the read option – stood by his locker on Wednesday and said he is sure Griffin will slide or run out of bounds rather than push for extra yards.
"He has to, if not he's going to risk getting injured again," said Morris, who later added: "He's not going to take shots he doesn't need to take."
And yet will RG3 heed this advice? Has he learned? Will it all settle around him until he gets onto the field on Monday night and the game is tight and the Redskins need a first down and he takes off running on a third-and-long, desperate to get to that orange marker on the ground?
[Watch: Must start quarterbacks for Week 1]
Will he slide? Will he keep running because that's what he has always done, certain of his invulnerability?
The answer might say everything about his career, the Redskins' season and Shanahan's future in Washington. Because other than the New England Patriots and Tom Brady, no team might need a player more than the Redskins need Griffin.
Can he change himself enough to be there?