The Giants.com staff debates Big Blue topics heading into Sunday's game:

The Giants' game plan changes with Nick Foles now playing quarterback for the Eagles.

JOHN SCHMEELK: Fact - The gameplan for the Giants will change in one important way: how they play RPO's. What are RPO's? Run-Pass Options. It's a play where the quarterback can make a decision post snap whether to hand the ball off to the running back, run himself, or then throw to a receiver based on what he sees from the defense. Obviously, the Giants will still have to respect the play action portion of the fake, but Foles is not near the running threat that Wentz was. Otherwise, their gameplan won't change.

DAN SALOMONE: Fiction - Even with Houdini, which is what the Giants call Carson Wentz, the game plan would begin with stopping the run. Interim head coach and defensive coordinator Steve Spagnuolo said as much this week after the news broke about the season-ending injury to a bona fide MVP candidate. Philadelphia uses a committee approach in the backfield, and the Giants have to make sure they know which one is in the game at all times.

LANCE MEDOW: Fiction -I understand when a starting quarterback goes down, due to an injury, everyone begins to wonder whether the offense will perform at the same level with the backup in but I think a lot of people are overlooking Nick Foles, who is a polished veteran that has familiarity with the organization, given he was their starter in 2013 and part of 2014.  The former third-round pick threw for 27 touchdowns with just two interceptions in 2013 highlighted by an NFL record tying seven touchdown passes against the Raiders.  Although he's not as mobile as Carson Wentz, the Giants' defense still needs to account for his strong arm, all the talent around him, and his ability to run the offense efficiently.  Plus, no matter who's under center, New York still needs to stop the Eagles' run game which ranks second in the NFL (143 yards per game).

*Wide receiver Alshon Jeffery is the most dangerous player on Philadelphia's roster. *

JOHN SCHMEELK: Fiction - This isn't even close. Jeffery has only 52 catches for 732 yards, though he does have eight touchdowns. Zach Ertz is a more dangerous player, in my opinion. The list on defense starts with the entire defensive line and probably includes Malcolm Jenkins too. Brandon Graham and Fletcher Cox scare me more than Jeffery, who has the size and route running ability but lacks the top end speed to run past defensive backs consistently.

DAN SALOMONE: Fact - Jeffery is one of those players who is open even when he's covered. His catch radius gives the quarterback a green light on pretty much every play. That makes him especially dangerous in the red zone, where has caught six of his eight touchdowns this season.

LANCE MEDOW: Fiction -Alshon Jeffery leads the Eagles with 732 receiving yards and a has a team-high eight touchdowns but right behind him is tight end Zach Ertz, who is having a Pro Bowl season.  The latter leads the team with 57 receptions and is second in receiving yards (663) and touchdowns (7).  He also had eight catches for 55 yards with a touchdown against the Giants in Week 3 and has already built chemistry with Nick Foles given they played together in 2013 and 2014, in Philly.  Don't overlook, the Giants have struggled this season against opposing tight ends, who have scored 11 touchdowns in 13 games.

Defensive tackle Damon Harrison is the most important player for the Giants on Sunday.

JOHN SCHMEELK: Fiction - Harrison will likely be the best player out there for the Giants on Sunday, like he has been most of the year but he won't be the most important. The quarterback is always the most important. He is always important in stopping the run but he needs help from his fellow defensive linemen and linebackers for it to make a true difference. The play of the Giants' offensive tackles against the Eagles stable of pass rushers (Brandon Graham, Vinny Curry, Chris Long and Derek Barnett).

DAN SALOMONE: Fact - Now wearing a captains patch, Harrison is one of the best players anytime he walks onto the field. Like we talked about earlier, the Giants need to plug the run game if they want to have any shot on Sunday. And there aren't many plugs currently better than Harrison, if any.

LANCE MEDOW: Fiction -I think stopping the Eagles' run game is priority number one for the Giants defense and, while Snacks plays an integral role in accomplishing that feat, having BJ Goodson on the field, at middle linebacker, is much more important.*  *The latter didn't play against Philly in Week 3 and the Eagles ran for 193 yards on 39 carries (4.9 yards per carry) with two touchdowns.  Goodson's positioning, in the second level of the defense, is key to communication in stopping the run as opposed to Snacks, who teams can simply avoid by running to the outside or the opposite direction.  Goodson is still nursing an ankle injury but has been a limited participant in practice this week and could very well return after missing last week's game against the Cowboys.

Giants vs. Eagles is historically the best rivalry in the NFL.

JOHN SCHMEELK: Fiction - This is hard to say. I know some Giants fans that believe the Cowboys rivalry is bigger, and some others even say the Redskins. The proximity of the two teams makes a difference too. Packers fans will argue their rivalry with the Bears or Vikings. The Steelers would reference the Ravens or Bengals. The Broncos would say the Chiefs or Raiders. It all depends on the fan and the team. I will say this, the Eagles-Giants matchup is right there with the best of them.

DAN SALOMONE: Fiction - After 194 meetings since 1921, the Packers and Bears were tied 94-94-6 heading into this season. How's that for a rivalry? The two winningest franchises in the NFL combine for 1,536 victories and 22 NFL championships. Lambeau Field. Soldier Field. Cold weather. This rivalry is what football is all about.

LANCE MEDOW: Fiction -Giants vs Eagles is the oldest rivalry in the NFC East so there's a lot of substance there but I wouldn't put it at the top of the list when you take into consideration the entire history of the league, especially postseason match-ups.  I'd put Cowboys vs 49ers (met in three straight NFC Championship Games in the 1990s), Cowboys vs Packers (met in the playoffs three straight years in the 1990s) and Giants vs 49ers (met nine times between 1981 and 1988 including three playoff games) ahead of the NFC East rivalry.  The Giants and Eagles have met four times in the postseason but that's been spread out over the course of nearly three decades and just one game was decided by a field goal.