Voices: Joseph Lowery

Four tactical trends that defined the 2021 MLS season

As soon as Alexander Callens’ penalty kick hit the back of the net at Providence Park, attention around Major League Soccer turned toward the offseason. Before you could say “New York City FC are MLS Cup champions," a half-day trade window had already opened and closed. On top of that, there's the 2021 MLS Expansion Draft and the opening of free agency. There is no rest for the (soccer-crazed) wicked.

Things are moving – players are changing teams and Nashville, well, they’re stockpiling allocation money, presumably to eat alongside hot chicken – but let’s not leave 2021 behind quite yet. This transition period between the end of one season and the start of the next is the perfect time to look back at some on-field trends that happened across MLS. With the help of Second Spectrum’s data, let’s pull out some of this season’s biggest trends and cast an eye toward an on-field development that we could see in 2022.

1
The rise of disruptors

You probably didn’t notice, but there was actually less soccer in MLS this year than last year, at least on a per-game basis. In 2021, the ball spent just 55 minutes in play compared to 56.3 minutes in 2020. That doesn’t feel like a crazy big difference, but a lot can happen in almost 80 seconds. Because the games were shorter, MLS saw fewer passes per game, fewer possessions per game, and fewer pressures per game in 2021 than they did the year before.

What’s behind this trend? Well, mostly the Red Bulls and D.C. United. Of the 15 games in the last two seasons that had the shortest amount of time with the ball in play, 14 of them were from 2021. And of those 14, 11 of them involved at least one of Gerhard Struber’s New York Red Bulls and Hernan Losada’s D.C. United. So while the amount of on-field play dipped this season, teams that like to disrupt games with heavy metal tactics made a big impact.

2
More aggressive passing

Outside of situations when they’re protecting a lead, teams don’t want to waste time. Sometimes we get confused, I think, and fall into the trap of believing possession-oriented teams don’t want to quickly move the ball forward toward the goal. They do. Peter Vermes’ Sporting Kansas City and Josh Wolff’s Austin FC, for example, want to get the ball from Point A to Point B just like the Red Bulls and D.C. United do…their method is just different.

No matter how you want to play, a great way to boost your team’s ability to get the ball toward goal and into shooting positions is to play forward more aggressively. MLS teams did exactly that in 2021. The league’s progressive passing frequency was up ever-so-slightly in 2021 compared to 2020 and teams completed passes between the lines more regularly, hit backline-breaking passes at a higher rate, and passed backward less.

To go alongside the idea that teams are starting to pass more forcefully, MLS teams generated more shots and more xG from counter-attacking and high regain (think counter-pressing) phases on a per 90-minute basis in 2021 than they did in 2020.

3
Focus on off-ball runs

One of the best things about Second Spectrum’s data is that it tells us something about what’s happening off the ball in addition to all of the other wonderful on-ball insights it gives us. As I looked through their various categories of off-ball runs, one thing stood out to me: players are making more high speed, off-ball runs.

In 2021, MLS saw a decrease in its total number of off-ball runs (which is no surprise given the rise of disruptive teams), but still had slight increases in high-speed run frequency and average run speed relative to 2020. An even bigger increase came in sprinting distance on off-ball runs. In 2020, MLS averaged 928 meters of sprinting distance per 90 minutes on their runs. In 2021, that number went up to 968 meters per 90 minutes.

Going one layer deeper, coaches are clearly prioritizing off-ball movement from their forward line. Forwards, more than any other position group, saw an increase in their off-ball stats and increased their total runs per game, high-speed runs, run speed, and distance in 2021 relative to 2020.

4
Three at the back

I wrote about the rise of three-center back shapes in MLS earlier this year, but now that the season is over, I want to revisit that topic here. By early September, every team in the league had used a three-center back shape in possession. D.C. United, the Colorado Rapids, Nashville SC, LAFC and the Seattle Sounders all greatly increased their usage of three-at-the-back shapes this season and took their place in the top 10 teams that most relied on three-center back shapes over the last two years.

Looking at the league as a whole, there were 207.6 possessions per game in MLS this year. Precisely 75.5 of those (36.4%) involved an offensive team using a three-center back shape. Last year, there were 214 possessions per game – and only 20% involved an offensive team using a three-at-the-back shape.

I don’t know if we’ll see three-at-the-back shapes continue to rise in 2022, but it does seem likely MLS will continue to push toward the “more aggressive on and off the ball” end of the on-field spectrum. The league has already taken strides in that direction and as players continue to get faster (the four fastest players recorded in Second Spectrum’s dataset all took the field this season) it makes sense that managers will leverage that speed into on-field output.

We’ve already seen a bump in aggressive passing and off-ball movement, so next year I would expect to see more in the way of aggressive ball-carrying. Continuing to emphasize assertive, vertical moves toward goal could eventually lead to an increase in the average number of defenders bypassed per offensive touch and could lengthen the average forward distance traveled per touch.

Will there actually be more impactful dribbles in 2022? We’ll have to wait until next year to find out and to learn about other trends that will shape MLS’ 2022 campaign.