Fancy stats preview of MLS Cup

If you had told me a month ago that I’d be writing an article this week, but it wouldn’t be a post-mortem of Seattle’s 2019 campaign, I would not have believed you. The Seattle Sounders have a certain knack for defying the odds late in the season. This isn’t to suggest that the statistics are wrong, after all, they’re just numbers and those numbers are accurate, but Seattle — either through luck, the force of will, experience, or most likely a mix of all of those things — have once again advanced to the MLS Cup final. It’s the third time in four years, and that’s actually rather crazy when you consider how MLS structures its league in a way that aims to prevent such things from happening.

I am an editor at a site called American Soccer Analysis. If you aren’t familiar, this is a site where lots of very smart people track advanced statistics, develop formulas and theorems in an attempt to understand soccer in a more objective way, and I correct their spelling. One of the things our site features is a playoff probability model. Explaining how it works would be difficult for two reasons:

A) It would take another entire article.

B) I don’t understand how it works.

You may have seen it if you follow me or any other ASA writers on Twitter, and even if you haven’t seen ASA’s, you’ve very likely seen 538’s model. These models did not give Seattle a very good chance of making it to the final. Going into the conference finals, our model had Seattle and Toronto with a 13% and 21% chance of advancing respectively (for the record 538’s model liked the underdogs’ chances a tad bit better, giving them a 19% and 30% chance, respectively).

Those odds are not great on their own. It gets better (or worse depending on your viewpoint I suppose...) when we work out the compound probability of both of those things occurring and Seattle hosting MLS Cup? 3.77%. MLS man. MLS.

Pretty cool eh? Let’s take a look at some more numbers that led to this improbable occasion.

Strong Side/Left Side

Readers of this site are probably aware that this season Seattle has favored the left side more than any other team in the league. They’ve been pretty consistent on this front over the last three seasons. The big change here almost certainly occurs between 2016 and 2017 with the acquisition of Nicolas Lodeiro at midseason, who seems to really prefer that flank. Add in some dynamic attacking left-backs in Joevin Jones and Brad Smith, and you can see that Seattle knows which side is their strongest one.

Nico Lodeiro: Sounders Hero

Let’s take a minute to remember that one time on Twitter when somebody claimed that Nico Lodeiro was the laziest player in Major League Soccer. I hope all of you enjoyed a nice haughty chuckle. Nico Lodeiro is an engine and one of the busiest players in the league. Nico handles 14.5% of Seattle’s touches. That’s the highest in the league for players over 2,000 minutes.

Being on the ball that much gives you a lot of opportunities to generate chances. It also gives you a lot of opportunities to get hacked. Yes, unfortunately for Lodeiro, he is your 2019 MLS “Getting Fouled Champion”. We should really come up with a better name for this award. How about the Golden Shinguard?

Of course, I’d be remiss if I didn’t also acknowledge that he also carried the Sounders’ heaviest load for generating chances. If we look at total xG (expected goals) + xA (expected assists), his return of 15.5 led all Sounders in 2019. Lodeiro’s influence on the Sounders cannot be overstated. Let’s take a look back at the best five individual offensive seasons since 2011.

Lodeiro is pretty good.

Set Piece Struggles

Lodeiro has proven quite the prolific earner of fouls, but what did Seattle do with these opportunities? This season? Not a whole lot. Off of free kicks, Seattle generated exactly zero goals this season. This is tied with Houston for the worst in the league in this particular department. If that sounds bad, it’s because it is technically quite bad, the worst it could possibly be actually. Things look a little better when we throw corners into the mix. Seattle converted six times from corner kicks this season. That still leaves them a little bit below league average (7.12) with the extremes being NYCFC with only two and Colorado with an altogether absurd 18. Seattle also weren’t blessed with a lot of opportunities from the penalty spot. They converted all three they were given, but those three attempts only dwarfed San Jose who had but a single penalty awarded to them this season. LAFC and Atlanta — whose fans are very well known to complain about how they don’t get any calls — were way ahead of everybody else in this department with 11 and 10 respectively. An interesting aside here though is that no team has given up more penalties in ASA’s dataset (back to 2011) than Toronto who conceded 13 penalties this year. That’s a very high number when you consider that ideally, you want it as close to zero as possible. Maybe Lodeiro will get a chance to make it 4-for-4 on Sunday.

While Seattle’s profitability from set-pieces has been better in recent history, they’ve not ever really been fundamental to the team’s successes.

Raul Ruidiaz: Good at Goals

There was a period of time between Obafemi Martins leaving for China and Raul Ruidaiz’s arrival in Seattle, that frustrated Sounders fans greatly. There was a sense that Seattle didn’t have a reliable No. 9. I’m not sure I’m in agreement with that assessment as Will Bruin was actually very, very good when called upon, but Ruidiaz’s arrival came at exactly the right time and he has been as good if not better than advertised. One of the most disappointing things about Seattle’s 2019 was that Ruidiaz didn’t get to participate in as much of it as I think most Seattle fans would have liked. When he was on the field though … he was excellent. From open play (which is fair since Ruidiaz doesn’t take penalties for Seattle) there was nobody better at generating xG in the league. There was someone AS good at generating high leverage chances, and well, I think Raul would be OK being tied w/ this guy.

Oh Wondo, you just don’t quit do you?

Let’s see where Ruidiaz falls in relation to other Sounders’ goal-scorers since 2011:

I’m not sure if even a healthy-for-a-full-season Raul Ruidiaz has a Josef- or Vela-like 30-goal season in him (indeed it’s almost impossible to do without the aid of a lot of penalties), but if he can put in 20 per year from open play he’s going to be considered an elite MLS striker.

Stefan Frei: Human?

Here are two things I’m going to say about Stefan Frei that are both true.

1. Stefan Frei is an elite MLS GK and has been the best GK in Major League Soccer since his arrival from Toronto in 2014.
2. 2019 was not Stefan Frei’s best season.

I’ve written about Stefan Frei for this site before, and in it I pled for him to be named GK of the year in 2018. He did not win. This was preposterous and shows just how difficult it is for many people to grade GKs well. I like to use G-xG. This is basically a metric that takes into account the number of shots faced, quality of shots faced, and a rough but decent estimate on how many goals a GK saves a team over a set period of time. Since 2014 Stefan Frei has maintained a G-xG of -0.17 per game. This puts him in the company of GK like Bill Hamid, Nick Rimando, and Tim Melia.

You could make a credible argument that Hamid beats out Frei by a nose, but I’m going to stand by Frei and say that maintaining that level over four thousand more minutes gives him the nod.

Let’s get back to this season though. It’s true that Stefan Frei isn’t exactly having his best season since arriving in Seattle. It’s his third-best season. Stefan Frei’s third-best season is considerably better than most GK’s career years. Stefan Frei is the main reason Seattle made it through FC Dallas, and if they’re going to lift a cup again on Sunday, he’s probably going to be a big factor in that too.

It’s not hard to see why Stefan Frei’s numbers dropped a little bit this year. He faced more shots than at any time in his Seattle career and was forced to make more saves. The reasons for this shouldn’t be difficult to surmise. Chad Marshall’s retirement combined with bringing in a talented but young CB, injuries, and, uh, other absences for Roman Torres, kept Seattle’s backline in a constant state of flux throughout the year. Seattle’s defense as a whole struggled at times this season, but Frei did everything you could ask to keep the matches as close as possible. It may not have been a career year, but when all of your years are good, that’s OK.

Looking at the Whole Picture

This was a difficult year to judge for me. My eye test would have suggested that this was easily the worst season for Seattle since Schmetzer took over full time in 2017, but data actually suggests that while not as good as 2017, 2019 was actually a good bit better than 2018. This is why I put little faith in eye tests. Least of all my own.

A +5.2 GD-xGD is reasonably close to even over the course of a full season and suggests that while still over-performing a bit, Seattle probably scored and conceded about as many goals as they “deserved”. Compare this to 2018 where their GD-xGD was an absurd +19.3. That suggested two main things to me. The first being frankly, a lot of good fortune, the second being that Stefan Frei was in God Mode that year. This year things were a little bit less volatile, and I think that’s good. Seattle’s defense was a little bit more unpredictable this season, but I think you can say that it has improved and stabilized somewhat down the stretch (that FC Dallas match notwithstanding) and given how well they managed to lock down LAFC in their last outing, it isn’t unreasonable to have a little more faith in that backline than the numbers suggest.

The Matchup

There isn’t a whole lot to separate Seattle and Toronto from a data perspective. Any betting lines and/or probability models giving Seattle a significant edge will mainly be doing it based on Seattle hosting. Playing at home is a pretty big advantage in Major League Soccer. Let’s take a look at the splits based on home/away.

Now you can start to see where you can get some separation. Seattle and Toronto have both dealt with some similar situations this season. There were long stretches of time where both teams looked to be in very bad shape. Both teams dealt with injuries to key players and a rotating cast of defenders.

So Who’s Going to Win?

Nope. No way. I’m not putting that juju on anybody. This is a cup final and it’s a Major League Soccer cup final at that. All I’m willing to suggest is that this will probably be a much better performance from Seattle than in either of their previous MLS final matchups. This 2019 Seattle Sounders team might not be as impressive from a data perspective as the 2017 version, and yet, I still feel like this one has the ability to be better. Seattle have frequently had the “when healthy” qualifier thrown before a glowing assessment of their potential talent. Barring any unforeseen occurrences, this is about as “when healthy” Seattle is going to look. I’ll let other people make predictions. There are credible cases to be made for both teams coming out on top. Some people have suggested that compared to the prospect of LAFC vs Atlanta, this final will be boring. One prediction that I’m willing to make is that it will be anything but that.