Cornered: Thrice is nice

Our first off-season post is a return to a perennial subject; corner kicks.

The Riveting! tradition started back in 2022 after the end of that season. If you recall – and if you don’t, here’s the 2022 post – the original was prompted by what at the time appeared to the “eye test” to be one of the bigger changes between the “Rhian Wilkinson (2022) Thorns” and the “Mark Parsons (2016-2021) Thorns”:

“And that made me think about the Thorns and 2021 and how my first thought was “gee…we’re not really that dangerous on set pieces anymore, are we? WTF happened with that?”

Because it felt like whereas once opposing coaches shrieked “OMFG do NOT forget to mark Lindsey Horan on setpieces! Mark her! Mark or die, mes enfants!“ now our opponents lolled about carelessly letting the corner kicks fall where they may, unafraid of Portland setpieces.”

Well. After a hard look at the 2022 data we concluded that
1) the 2022 Thorns produced corner kicks at a historically average rate, and
2) that, in turn, suggested that there was not likely to be a statistically significant difference between 2021 and 2022.

It’s two years too late, but I wanted to note that I think that my second conclusion was wrong because I failed to look around at the league.

Here’s the 2021 league pass data ranked by “corner kicks per 90 minutes”:

Parsons’ Thorns led the league in both corners worked per match and shots created from dead ball plays (which includes corners but isn’t reduceable into free kick versus corner kick breakdowns).

And “led the league” is “led by a LOT” – Parsons squad worked 140% of the 2021 league average of corners per 90 minutes (7/5) and 144% of the league average of overall shots created (75/52.1).

So while Parsons’ final squad may have been within the mean of professional leagues worldwide it was at the top end of the NWSL in 2021.

What happened the following year? Here’s Wilkinson’s 2022 squad:

Kind of a hotchpotch. Still on top of the league in corners per 90, although significantly less above the mean than in 2021 (125%, 5.41/4.33) in a league where the corners per 90 was also down significantly from the previous season (86%, 4.33/5).

But way down in shots created from dead balls; from top to fifth-from-bottom, from 144% to only 91% of the league average (90.9%, 38/41.8).

So the combination of roster changes and coaching changes really did change how “dangerous” the Thorns were on setpieces between Parsons and Wilkinson, including corners…

But.

Look at the “PassDead” columns under “GCA Types”. That’s “goals created actions” by dead ball situations.

In 2021, 4 goals from the highest corner kick- and shots-per-dead-ball-percentage in the league.

In 2022, 5 goals from fewer corners and much fewer shots.

So, “dangerous”? Sorta. Somehow Wilkinson’s Thorns actually created more goals from what look like fewer corner kick/free kick opportunities. Go figure.

What’s happened since then?

The post-2023 study concluded that:

“Parsons to Wilkinson to Norris…the Thorns have remained pretty consistent from the corner across three gaffers and three seasons.

Neither among the league’s most dangerous nor down amongst the dregs, the Thorns’ corner kick production seems to be solidly in the league mean through that time. I think we’ve got the data we need to close this study for another year.”

Okay, the caveat being that, as we’ve just seen, Parsons 2021 squad created lots more chances; they just didn’t convert them.

So how did the Norris/Gale 2024 squad look? Here’s the raw data:

Hard to read, so I’ll break it down.

The Thorns generated 94 total corner kicks in 27 matches, ranging from a high of 7 (twice; Houston away and Bay FC here) to blanks against Houston here, and averaged 3.48 corners a match.

Those corners were overwhelmingly “long” into the box – over 85% were long – and they generated 31 shots, 13 on frame (and four blocked) along with eight other “dangerous chances”, meaning a Thorn got a head or foot to the ball and either shot directly at the keeper, hit the woodwork, or was tackled before the shot.

Those efforts produced precisely one goal, Morgan Weaver against Racing on Matchday 3. If you’re feeling generous you could include the what-really-should-have-been-Reina Reyes’-goal in Washington on Matchday 19.

Those totals were down sharply in two our of the three major categories from the previous season:
1. Corners per game: 2024 corners/game were down to 64% of 2023 (3.48 to 5.41),
2. Shots per corner were about the same – 0.329 shots per corner in 2024 to 0.32 shots per corner in 2023, but
3. Goals per corner were sharply down from 2024 by almost 75%: (1.1% goals from corners in 2024 to 4.2% of corner kicks in 2023). Even if you count the Reyes goal in Washington it brings the 2024 percentage up to only 2.1% of all corners, so about 50% of the 2023 ratio.

That’s pretty dire.

As we noted after 2022, that’s within professional league ranges, though well on the low end. How did that compare to the NWSL in 2024?

Not good, 13th of 14 overall even in a league that as a whole generated fewer corners in 2024 than 2023:

Down by about 10-15% league-wide.

But the Thorns suffered among the worst declines in corner kick generation between last season and 2023, almost two corners per 90 minutes less than they did previously. Only Racing and Angel City – 9th- and 13th-place finishers, respectively – were worse relative to the previous season than Portland.

My guess is that this largely reflects Norris- and Ken-Ball’s less-effective overall attack, as well as troubled by major injuries to Sophia Smith, Morgan Weaver, and Hina Sugita. The Thorns xG is practically identical across the 2023-24 seasons (about an average of 0.39) but significantly lower per 90 minutes – +0.09/90m in 2024 down from +0.58/90m in 2023.

Fewer dangerous chances means fewer opponent needs to block or clear over the byline, meaning fewer corners. And fewer dangerous chances from fewer corners means fewer goals.

And, of course, the Thorns have never replaced the setpiece specialists of the peak Parsons seasons, players like Tobin Heath, Emily Sonnett, and Horan herself.

Which, in turn, brings us right back to where we were after the quarterfinal loss; what are the Bhathals going to do about that..?

Next: 2024 Final Grades – The Goalkeepers