They've seen the highlight-worthy passes, the scintillating runs, and they've been so impressed that Osi Umenyiora has practically knighted the rookie quarterback, referring to him as "Sir Robert Griffin."
On Sunday, they'll meet RG3 in person for what likely will be the first of many battles to come.
The mere thought of seeing the Redskins' newest and brightest hope -- and perhaps the fastest quarterback in the league -- for several more years made Justin Tuck let out a big sigh.
"Yeah, yeah ... looks like it," Tuck said, of this being the first of many encounters. "It is amazing that [Tony] Romo is the least mobile quarterback now in the NFC East that I get to play."
Tuck practically shook his head while saying that. Despite the fact that Washington swept the season series last year, Giants-Redskins hasn't had the same oomph or impact as the Giants' division rivalries with the Dallas Cowboys and Philadelphia Eagles in recent years.
But Griffin's arrival changes that. It's been a while since the Giants had to worry about a dangerous playmaking Redskins quarterback.
Rex Grossman, Donovan McNabb, Jason Campbell, Mark Brunell, Patrick Ramsey, Tony Banks, Brad Johnson, Trent Green, Gus Frerotte and Heath Shuler have been among the QBs in Washington since Mark Rypien was throwing bombs back in the early 1990s.
Griffin may be the most dynamic quarterback the Redskins have ever had, and he could be a thorn in the Giants' side for the foreseeable future.
"It's different," Tuck said of Griffin's presence with the Redskins. "He is a game-changer. They haven't had a good game-changer at quarterback in a while. And he is that."
"But still young," Tuck added. "I don't know how much of a game-changer he will be, but he definitely makes it difficult for defenses."
The Giants have had plenty of practice prepping for dual-threat quarterbacks this season. They've played against Romo, Carolina's Cam Newton, Philadelphia's Michael Vick and San Francisco's Wildcat option quarterback, Colin Kaepernick.
But Griffin might have another gear of speed than those quarterbacks, and that's scary.
"Robert Griffin is a lot different than the guys that we have played at this point," defensive coordinator Perry Fewell said. "Not that those guys are not good athletes, but he is an extremely gifted athlete and he can go from zero to 60 right now."
That was on full display last Sunday, when Griffin scored on a sensational 76-yard touchdown run against the Vikings. From the moment he planted his foot on his drop-back near the 15-yard line, Griffin only needed 10.5 seconds, give or take, to reach the end zone.
"Ridiculous," Umenyiora said of the run. "You saw guys who are known as fast guys just trailing behind him, and you saw him blazing down the football field."
The Giants did a good job against the quarterback option that Newton ran, holding the Panthers to a total of 60 yards rushing. Kaepernick only had six yards rushing, while the Niners managed a grand total of 80 yards on the ground.
While the Eagles don't run the same scheme, Vick exposed the Giants' lack of containment, scrambling for 49 yards. Running back LeSean McCoy hurt the Giants badly with 123 yards rushing, doing damage on the edges as well.
Those two Eagles are playmakers with serious speed. Against Griffin, the Giants' containment must not break. And they won't have speedy linebackerJacquian Williams (knee) due to injury.
"We know we can play this type of game," Umenyiora said. "That's the only thing I can say for sure. But we haven't seen a guy with this type of speed before."
"We haven't seen this particular offense, because a lot of times they fake it, throw the football," Umenyiora added. "They're doing a lot of things that a lot of teams don't do."
And Griffin does things the Giants simply have never had to deal with when facing the Redskins. It was already tough enough having to face Vick and Romo twice each season.
Now Tuck and the Giants defense has to face three mobile quarterbacks in the division six times this season and potentially next year as well.
As Tuck was talking about how difficult of a chore that will be, a reporter pointed across the Giants' locker room to the slowest quarterback in the division -- Eli Manning.
"Well, I don't get to play him," Tuck said with a smile. "That is the guy that we wouldn't worry about contain [against]."
"[The Redskins] did a lot of upgrades," Tuck added. "For years to come, [the Giants-Redskins rivalry] is going to be pretty good."