NFL stats can be skewed by several factors. A good defense might have a bad ranking because of a poor offense. A running game could go unused if a team is forced to play from behind. Even a great offense could fail to score because of bad special teams.

But when it comes to the Giants’ defense, which has allowed more yards than 29 other teams, there aren't a lot of mitigating factors.

“We’ve prepared better than what we’ve played,” defensive coordinator Perry Fewell said on Thursday. “We haven’t made plays. I think if you look at the tape, we’re in position to make plays, and we haven’t made plays.”

Opposing offenses have been making plays.

The Giants have yielded 57 plays of 20 or more yards this season (29th in the NFL) and 13 plays of 40 or more yards (31st). Some of that can be blamed on the disappointing pass rush; some of it can be attributed to various injuries to linebackers and defensive backs.

But for the most part, Fewell blames his players’ inability to make stops.

“It’s frustrating for me and for the defense to give up the big play,” Fewell said. “That’s been our nemesis all year. Have we worked to eliminate the big play? Yes, we have. Have we been able to do that? No, we haven’t. I can’t tell you why, but yeah, that can be a point of frustration.”

There are plenty of technical issues to debate.

Fewell implemented a 4-4 scheme in last week’s loss to the Ravens, but considering Baltimore had two running backs break the century mark, the strategy didn't work.

The three-safety formation had success against the Packers in Week 12 (New York held Green Bay to 10 points in a win), but S Kenny Phillips (knee) hasn’t been healthy enough for any prolonged use of the scheme.

Fewell was asked about the decline of DE Justin Tuck (three sacks), CB Corey Webster and LB Michael Boley, but besides mentioning a few injuries, he wasn’t comfortable pointing the finger at individual players.

In the end, Fewell doesn’t have a lot of answers. Just questions -- such as, where did the turnovers go?

“Again, we’ve been in position, we haven’t made a football play for the last couple of weeks,” Fewell said. “We’ve been in position to make football plays, but it hasn’t gone our way. They say turnovers come in bunches and sometimes we get them in bunches, and right now, we’re on a dry spell, a two-game dry spell. We’re going to work like the dickens to get turnovers in this football game.”

The 8-7 Giants host the 4-11 Eagles on Sunday, and if they’re to get into the playoffs, they’ll need a win, a Cowboys loss (or tie) as well as a Vikings loss and a Bears loss.

The season will likely come to an end on Sunday, which means Fewell has guided the Giants defense to a Super Bowl title and a 30th overall ranking over the last two years.

Whether that’s enough for him to keep his job is anyone’s guess.

“We won a Super Bowl in this system,” DE/DT/SLB Mathias Kiwanuka said. “I think that’s the main thing. We have the same signal caller that we did last year. So for us when things are out of your control, there’s no sense in worrying about that while you’re still going through the thick of it.”

Follow the Giants and Alex Raskin @CBSGiants and @AlexRaskinNYC.