Many were quick to write off the New England Patriots as true Super Bowl contenders following their 23-16 loss to the Kansas City Chiefs on December 8.

After all, New England has lost three of their last five games, the offense averaging a paltry 17.6 points per game in that time span.

The Patriots now have just a one game lead over the 9-3 Buffalo Bills for first place in the Amrican Football Conference East Division. That is some shaky ground to stand on for a team that looked to be in control of the AFC’s top overall seed not too long ago.

Quarterback Tom Brady is averaging a career-worst 3.6 Touchdown percentage. His Quarterback Rating is just 86.5, his worst mark since 2003.

Even the most die-hard Patriots fans are beginning to admit that the dreaded decline has likely come with TB12.

The Patriots’ offense certainly does not seem to be good enough to win them a Super Bowl… or does it?

There is some precedent in recent history of teams with mediocre (and even a few poor) offenses winning the Super Bowl thanks to outstanding defensive units.

The 2015 Broncos, whose Hall-of-Fame quarterback Petyon Manning was also having a career-worst season, managed to win the Super Bowl thanks to their incredible defense and the touted secondary unit, the “No Fly Zone.”

Could this year’s Patriots have similar Super Bowl success predicated on strong defense that makes up for an abysmal offense?

Despite winning the Super Bowl, Peyton Manning had a downright terrible year in 2015, throwing for just 2,249 yards, nine TD’s, and 17 interceptions. To be fair, Manning missed six games with a foot injury that year (their backup QB, Brock Osweiler, was arguably better). However he still had just a 67.9 QBR, the lowest of his career.

That year, the Broncos’ defense led the league in total yards per game (283.1) and passing yards per game (199.6), and were third in rushing ypg allowed (83.6). To compare, the Patriots’ defense has held opponents to a league-best 264.8 total ypg. The Patriots are second in passing ypg (171.8) and fourth in rushing (93).

The Patriots hold opponents to over 20 fewer passing yards per game, but they also allow ten more rushing yards per game the the 2015 Broncos did.

When Manning returned for the playoffs, the Broncos leaned on their defense to win games. Being the Hall of Fame QB that he is, he understood that he needed to be more of a game manager rather than try to throw for 400+ yards. He recognized that the team’s defense was their key to success.

With teams like the Ravens and Chiefs lurking come playoff time, the Patriots may want to employ a similar strategy as the 2015 Broncos.

While the defense has been great, it likely needs to be even better for the team to have a real shot of winning it all. Brady needs to adjust to and accept his updated role as a gamer manager, and the Pats need to run the ball more effectively.

If the Patriots’ defense can hold the course like it has thus far, the team should be in a better spot than many might think heading into playoffs. After all, offense sells tickets—but defense wins championships.