Total offense statistics from the 2017 NFL season explain why the Ravens are so focused on that side of the ball this offseason. Their No. 27 league ranking was nothing if not a call to action.

As a result, free agency, the draft and the local football conversation have been all about wide receivers, tight ends and quarterbacks this year, with running backs and the O-line also receiving attention.

But while the Ravens' ability to field a better offense certainly will help determine how their 2018 season goes, I'm nagged by the suspicion that everything will still boil down to an all-too-familiar question: Can their defense stop the Pittsburgh Steelers offense when it counts?

The Ravens' past two seasons pretty much came down to that. Their offense put up enough points to win in Pittsburgh last December, and had they won that night and made the playoffs, we'd be having different conversations now. But the Ravens lost, 39-38, and eventually missed the playoffs. A year earlier, their 31-27 loss in Pittsburgh on Christmas Day knocked them out of the playoffs.

Although the Ravens and Steelers weirdly will complete their home-and-home series by Nov. 4 in 2018, the Ravens' season always seemingly is shaped by how they fare against their AFC North rivals, and it's their defense, for sure, that needs to perform better in that situation.

The organization is taking the opposite path on that side of the ball this offseason. Unlike on offense, where big changes are afoot, the Ravens are maintaining the status quo on defense, bringing back every player who took a snap in 2017 except Lardarius Webb. Any new blood will emerge from a sprinkling of third-day draft picks and veterans returning from injuries.

The message is clear: The Ravens believe the architecture of a playoff-caliber defense is already in place. There's evidence supporting the notion. Baltimore led the NFL in takeaways in 2017 and ranked No. 12 in fewest yards allowed.

Yet the defense's fourth-quarter collapse in Pittsburgh illustrated that it needs to do better, and that wasn't the only example of it failing to protect a lead in 2017.

Without any major personnel changes, how do the Ravens plan to improve enough on defense in 2018 to enable them to stop the Steelers when it counts?

They're certainly counting on a change at the top making a difference. Though Dean Pees is a respected coach whom the players embraced as their defensive coordinator, several have already commented positively on the switch to Wink Martindale.

Last month, safety Eric Weddle said Martindale is "changing a lot of stuff" and "bringing a lot of new elements that we haven't had." Earlier this week, Terrell Suggs said Martindale is "taking the handcuffs off the guys." Strong imagery.

"Sometimes a player can be shackled just by the rules and confines of the defense," Suggs added. "I think Wink is going to allow us to go make plays and be the fast-moving defense that this city and the fans love."

It's still up to the players to enact Martindale's strategies, of course. Where might the improvement come from?

It could come in the secondary, which appears especially deep in quality cornerbacks and safeties. Marlon Humphrey could become a force in his second season. Tavon Young's return adds a natural slot corner. Jimmy Smith's health, as always, is an X factor.

The run defense was shaky at times in 2017 but mostly solid when tackle Brandon Williams suited up. (He missed four games with a foot injury.) The Ravens hope Brent Urban's return from a foot injury further tightens things up.

To me, the pass rush is the biggest question mark. Although Suggs still leads the way, he turns 36 in October. Matthew Judon has a dozen sacks in two seasons, but the Ravens need a bigger inside push and also need second-year linebackers Tyus Bowser and Tim Williams to start living up to being second-day draft picks.