I pointed out in The Graphical (and mentioned a couple times in the player ratings) that Nashville SC attempted a ton of crosses against Charleston, and completed them at a rate pretty close to what they’ve done over the course of the entire year. That is to say: this was a heavily-used and highly-successful offensive strategy, there just wasn’t quite the finishing that you’d like to see.
Why was that? It starts with the three-man backline of Charleston. Here’s how the Battery lined up opposite Nashville’s now-standard 4-4-2:
As you can see, that’s a three-man backline. Another of NSC’s most cross-heavy games of this year? Against Pittsburgh Riverhounds, who themselves are going heavily with a 3-5-2 (or 5-3-2 – just a nomenclature difference for the most part, though the distinction will become important in a minute).
Why does Nashville SC cross so much against these teams? For starters, it opens up a lot of channels to cross. With NSC’s speed on the wings, they’re able to get the ball into dangerous crossing positions against the three-man backline. The nature of having fewer guys with primary defensive responsibility means that either a defensive midfielder has to recover and get wide (pictured below), or one of the three centerbacks has to come from a pretty compact position, leaving the remaining two players in the defense with two strikers:
The other factor that comes into play against the odd backline is that it means the defense is rarely man-marking a pair of opposing strikers. Lebo Moloto and Ropapa Mensah weren’t exactly running free into the box, but certainly markers had to pick them up later in the course of the play, rather than man-marking them throughout (as you’d more likely see – with some switching when the runs cross – from an even backline).
See this animation as Mensah (begins at right edge of the screen) is only picked up by the left centerback as the ball is played, while Moloto (enters from the left side of the screen) is unmarked in the box, aside from a defensive midfielder who’s tentatively trailing him, and the middle centerback who would have to react very quickly and close a ton of space if the ball goes to No. 10:
This zonal marking and evening-up of the numbers (you can see LaGrassa, starting from the bottom and eventually getting his head to this cross, is picked up by a central defensive midfielder, as indicated in the diagram above) makes for a really complicated set of communications, shifts, and responsibility changes during the course of the play for the defense. That’s something that Charleston clearly thinks it has the ability to pull off – and the results, only four goals allowed in seven games since making the switch, vindicate that thought process.
The defensive formation is also designed to invite crosses. Why is that? I can’t speak for Charleston’s coaching staff, but as a general rule, an aerial cross is one of the harder plays to turn into an actual goal (according to expected goals data, at least). Ground crosses, shot rebounds (one of which is unlikely to result from a headed chance whipped into the box), and possessing the ball inside the 18 are all considered more likely to result in goals. Charleston is baiting you into it because they think you aren’t good enough to score, basically.
That said, you’re going to get a lot of good chances still:
That ball played from Matt LaGrassa to Ropapa Mensah stayed on the ground (a much higher-percentage play, according to expected goals), and he’s running into acres of space because of the three-man backline – the outside centerbacks are the be-afro’d Neveal Hackshaw, bumped out to defend LaGrassa’s cross, and Skylar Thomas with his dreadlocks in a high ponytail there, in a chasing position because of the space created with no man marking. This was complicated more for the Battery by the fact that their middle centerback, Taylor Mueller (whoe just in front of Mensah, and would ultimately clear this cross away) was playing deeper than the other two in a sweeper position.
The three-man backline means you can get a lot of numbers in the defensive area compactly, but you need a lot of help from midfielders – and generally wide midfielders, whom the Battery didn’t activate defensively all that much – to prevent both the crosser and the runner from having too easy a time. Nashville SC created a lot of chances from the cross, and better finishing would have done them a world of good.
Lots of space around Moloto, even though Charleston has numbers in the box. Precision crossing and clinical finishing can’t be beaten.
What does it mean for Pittsburgh?
Pittsburgh also runs a three-man backline, but they do it in a different way than the Battery: in fact, it’s what Nashville SC started the season doing, with two true wingbacks, a three-man central defense and central midfield, and two players up top.
As I’ve shown above, having two strikers (as Nashville SC has in every competitive game this year, whichever formation they’ve run) is a way to mess with the numbers at the back, because odd backlines have a tendency to not man-mark an even number of strikers. However, it’s defending the cross itself that allows Pittsburgh to be a different beast defensively: they’ve allowed a league-low five goals all season, the only team better than NSC on that end of the pitch. By playing with wingbacks, instead of four traditional midfielders (and the defensive deficiencies seen above, and that you’d expect from players who are either wingers of some variety, or central defenders who need to get to a wide area of the pitch in a hurry), they have natural players in place to put pressure on the crosser that Charleston didn’t. In a nutshell, they don’t need to either give the cross for free or sacrifice one of the centerbacks (leaving the other pair two-on-two with strikers, but not man-marking them) in order to play sound defense.
Of course, Nashville SC will have its own methods of coping with that: giving very little away defensively – as they’ve done basically all year – is where it starts, because that forces Pittsburgh to push numbers forward to generate anything on offense. Using speed on the counter (when Pittsburgh’s wingbacks are caught upfield offensively) will be an important strategy, getting crosses in while the wingbacks are upfield.
NSC will also have to get creative with its runs to generate offense outside of crosses, taking angles that the central defenders aren’t expecting, in order to find open space in the box. We saw more of that than you might expect in the first matchup of these two teams, but that was in the “Nashville can’t finish to save its life” portion of the season. Now that things are looking a little better there, completing the chances that they create (still not a strength) and preventing Pittsburgh from playing for a draw – or with a lead – changes the complexion of the game.