BALTIMORE – Maybe it's not yet to the level where it deserves a nickname, and maybe it's still going to be a unit that lacks a national profile. But the 2017 NFL season is four games old, and the Steelers defense is in the top 10 statistically in 10 categories in which the NFL ranks its teams' units, and it ranks in the top five in eight of those 10 categories.

Second in total yards per game. Second in yards per play. Second in net passing yards per game. Second in net passing yards per play. Third in sacks per pass play. Tied-for-fifth in first downs per game. Fifth in third down efficiency. Third in points per game.

And more significantly today, the defense is the No. 1 reason why the Steelers won a game at M&T Bank Stadium yesterday, which was their first victory over the Ravens in Baltimore since 2012. The final score was 26-9, and that it could've been a shutout if not for an obvious holding penalty that wasn't called on a 50-yard run by Alex Collins and a bizarre replay ruling that took a reception followed by and down-by-contact and turned it into an interception, well, that was just a sidebar to the real news of the day, and in fact the news of this young season for these Steelers.

There can be all kinds of caveats and qualifiers attached to what the Steelers defense has been accomplishing so far based on the quality of the opposition, but what's clear is that the unit is showing significant improvement in areas generally lumped under the umbrella of "making plays."

Making plays is code in the NFL for doing things such as sacking or pressuring the quarterback, intercepting or breaking up passes, making tackles for loss in the running game, forcing fumbles and recovering them. Too often in recent seasons, the Steelers defense would complete 60 minutes of football without doing any of those things, let alone doing enough of them to be a reason why the team won.

Take Sunday in Baltimore as an example. The Steelers sacked Joe Flacco four times and finished with six pressures; they had two interceptions and seven passes defensed; they made seven tackles for loss; they forced and recovered a fumble. The Steelers defense was initiating the action against the Ravens rather than simply trying to make tackles after completed passes. It's not so much anymore that the Steelers defense is working to minimize what the opposing offense does to it, but more and more it's becoming a situation where the opposing offense has to contend with a group of playmakers on the Steelers defense.

Beyond some of the individual player's accomplishments, the defense has shown the ability to rise up as a unit and contribute winning play during the typical ebb and flow of a football game, because often what happens at one stage of the game can chart the course for what follows.

Again, referring to the victory over the Ravens, the Steelers defense controlled Baltimore's offense through the early going, which was significant because an early lead would have allowed the Ravens to dictate the pace and flow of play. In their recent trips to Baltimore, the Steelers put themselves in a difficult position by falling behind early, but this time the defense prevented that from happening because on the first five offensive possessions the Ravens were forced to punt four times and the Steelers recorded a takeaway on the fifth. By that time, the Steelers held a 19-0 lead, and it was the Ravens who were being forced into a style that was predictable and not necessarily their strong suit.

Then in the fourth quarter, which is when so many NFL games are won or lost, a fourth quarter that began with the Ravens having cut their 19-point deficit to 10, the Steelers defense tightened the vice with two takeaways, a forced punt and a turnover on downs. That was all the Baltimore offense could produce on four possessions.

This is proof of progress, of improvement, of the Steelers becoming more of a complete team, and putting it together to leave Baltimore with a victory is a good sign. And what's encouraging is that much of the difference can be traced to some young people who still can improve as individuals, which in turn will result in the group getting better along the way.

Already, these Steelers have absorbed injuries to Stephon Tuitt and T.J. Watt and Mike Mitchell; they no longer have to ride or die with veterans on the downside of their careers; and they have improved themselves to the degree they no longer have to gamble or rely on gimmicks to do the things the good teams get done simply by winning individual matchups.

This season is still young, this Steelers defense remains very much a group in development, and because of that there can be expected to be peaks and valleys in the weeks and months ahead. But what's inarguable is that there is improvement, and that improvement already has been responsible for the winning of some games.

If that continues, there might yet be a nickname in their future.