How long can the Redskins keep this up?

Ryan Kerrigan, right, and the Redskins' defense put enough pressure on the Eagles to key a victory. AP Photo/Michael Perez

PHILADELPHIA -- It's now more real than it's ever been -- this idea that the Washington Redskins can win the NFC East for the first time since 1999 and make the playoffs in Robert Griffin III first year as their quarterback. They need only to win one more game -- on Dec. 30, at home against the Dallas Cowboys -- in order to make this a reality. Which is why statements like this one have begun to beg for deeper examination.

"We're not playing to make the playoffs," Redskins nose tackle Barry Cofield said after Sunday's 27-20 victory over the Philadelphia Eagles. "We're playing to win the Super Bowl."

Is he nuts? Would a 10-6 NFC East champion Redskins team be a legitimate threat to run through places like Atlanta, Green Bay, San Francisco or Seattle and win a Super Bowl against the Patriots, Broncos, Texans or Ravens? Cofield admits to dreaming -- in his "down time" -- about playoff matchups and how his team would match up against others they might see. Cofield's one of the Redskins with postseason experience, from his time with the Giants, so he knows what it means to go in as the hot team. And if the Redskins win next week, there won't be a hotter team in the NFC field. Redskins coach Mike Shanahan said these Redskins are a team that "expects to win" these days, and that's what gives Cofield his reason for optimism.

"That's definitely the case, and it's a different type of pressure, but that's the way good teams operate," Cofield said. "We've gained that mindset at the right time of year, and we're playing well enough to back it up."

But are they? Is this Redskins defense really playing playoff-caliber football? They gave up 411 yards to the Eagles on Sunday and have allowed an average of 383.1 yards per game for the season, making them statistically one of the worst defenses in the league. The reason they are 9-6 is that the defense has held on just enough in critical spots to support a very high-scoring offense. And because of a plus-14 turnover differential that ranks among the top five in the league. The Redskins' coaches have been working harder than ever with their defensive players on the importance of forcing turnovers since the team emerged 3-6 from its Week 10 bye, and the message is getting home.

"It's okay to bend, as long as you don't break," linebacker Perry Riley said with a smile. "And if you can get that turnover, it doesn't matter how much you bend. If you let them go down the field on you and you force a fumble or get an interception, it doesn't matter how far they got. If you take the ball away from them, they can't score."

This is indisputably true. The question is whether it's sustainable. Can a defense that allows nearly 400 yards a game force enough turnovers to beat Aaron Rodgers and Matt Ryan in consecutive weeks and make a run at a championship? This is not a question the Redskins haven't pondered. Cofield wrinkled his nose and nodded in acknowledgement when asked whether it was possible, but he quickly brought up last year's Super Bowl between the New York Giants (who allowed 376.4 yards per game in the 2011 regular season) and the New England Patriots (411.1).

"You always want to get stops," Cofield said. "You don't want them to be able to go down the field against you. But the two Super Bowl teams last year didn't have the greatest statistical defenses and there they were. As long as we have the will and the talent to play our butts off, we're confident that we can continue to make those plays."

That confidence is the biggest thing this Redskins defense has going for it right now. There were long stretches in Sunday's game in which they appeared incapable of stopping a Nick Foles-led, four-win Eagles team from picking up a third down or even a fourth down. They needed to stop Foles at the goal line with seconds left to avoid overtime, and had time not run out they may not have pulled it off. It is not a defense that makes you feel as though it can go out there and shut down an opposing offense.

But it is a defense that believes in its own playmaking ability. And that's because it's a defense that's making plays. The pass rush was a non-factor for most of the season after the early injury to Brian Orakpo. But they got five sacks Sunday and 16 of their 30 sacks this season have come during their current six-game winning streak. Griffin remains and will remain the biggest storyline the Redskins have -- regardless of how long their season runs. But he's been a constant pretty much all year. What's turned this Redskins team from a 3-6 mess into a team that's now guaranteed to finish with a winning record is a defense that has found a way each week to make just enough plays. In order to win the Super Bowl, they need to do that five more times, starting Sunday.

"It takes a lot of character on your football team to fight through what we have," Shanahan said. "We've got to get sacks, and we have to get turnovers, and we've been able to do that on defense. Today they probably had 20, 25 more plays than we did [actual number: 22], and that's a little bit unusual with our running game the way it's been. But we took advantage of the turnovers, which negated how many plays they had."

It has been a winning formula in the past, and with the unusual looks the Redskins would be able to throw at their fellow playoff teams on offense (assuming Griffin's knee keeps improving), it could be enough to make them a real threat in January. Assuming they get there, of course.

"The greatness of this feeling will wear off very quickly if we don't get it done next week," Cofield said.

He's talking about a defense that knows it needs to play better but, like the rest of this team right now, believes it's capable of absolutely anything.