Comparing To Actual xSO

Quick assessments for Serving, Passing, Offense, and Defense

On Monday, August 15th I’m going to host another small-group workshop. This will be available for premium subscribers only. Our topic is, “Rosters and Rotations.” I’ll share some of my thoughts on putting together a roster and forming those players into a starting lineup and then we’ll dive into attendee questions. Wondering about which player to play as the next-to middle and which player to play away from the setter? Debating between starting in Rotation 1 or 2? You’ll enjoy this session. Upgrade to a premium subscription now to attend.

Also: if you have questions but aren’t sure if you’ll be able to make them, start dropping them in the comments section or shoot me an email. I can make sure I cover those questions live and I’ll have the recording available for everybody after.

I’ve released three articles about Expected Sideout. Wow, that’s a lot of space dedicated to this topic! You can check out the first and second articles if you want, as they explain the concept a little more, but the most recent post probably sums up most of what you need to know.

The Final (For Now) Expected Sideout Post

Now let’s look at some actual use-case here and figure out how we can use it to plan training. The key here is the comparison of xSO or xFB to actual SO and FBK/FBSO.

Comparing To Actual

Here’s what some of this looks like, summarizing our VNL performance for the Canada MNT:

You can see that you have to compare your passers to opponent passers, or a general passing standard. And you have to compare your servers to opponent servers, or a general serving standard. If you just calculate your passing xSO or xFB and then compare it to your servers, then things will be out of whack, because the passing numbers don’t include missed serves and the serving numbers do.¹

Alright, so what the heck do all these numbers mean? And more importantly: how can we use that information to improve our training?

xFB v FB Kill

This is a comparison of how often you expected to kill the ball based on your pass quality vs how much you actually killed it.

In this case, we passed well enough to expect to kill 44.5% of our receptions, but we actually killed 42.4%. So we could say that our offense underperformed our passing by 2% in FBK. On the flip side, our opponents passed well enough to expect to kill 46.6% of their receptions, but they actually killed 48.5%. So we could say that their offensive overperformed, or, more useful to us, our defense underperformed our serving by 2% in FBK prevention.

What’s also interesting is that all these gaps were about the same. Our passing was about 2% below our opponents. Our offense underperformed passing by 2%, and our defense underperformed by 2%. This is starting to give me a picture of a Balanced Profile, without a clear strength or weakness in any of these phases.

Team Profile: Balanced

xSO v Earned Sideout

Let’s expand to not just look at the ability to kill the ball in First Ball, but also to just win the rally through Sideout, regardless of whether it was a First Ball Sideout or the point was won in Transition.

And now we see something a little different. Our Earned Sideout was 56.0% compared to 59.7% xSO, which is a 4% gap. And our opponents had an Earned Sideout of 66.0% compared to 61.5%, which is a 4.5% gap. Or, to put it another way:

Purely based on pass quality, we’d expect our opponents to Sideout about 2% better², but the gap is 10%! What gives?

Bringing In The Serving Metrics

One thing I’ll check quickly is Serve-In%. We served in at 79% and our opponents served 83% of serves in the court. So when you look at the overall Sideout gap, that’s part of it. Their passers had a moderate edge on ours, but we also missed more serves in doing so. And you see this when you look at serving stats as well:

Canada Passing v Opponents: -1.8% (59.7 to 61.5)

Canada Serving v Opponents: -3.1% (66.4 to 69.5)

You could put this another way and say that we lost 1.3 points of Sideout to our opponents by missing more serves and 1.8 points of Sideout to our opponents by serving easy. Or, in graphical form, if we were going to make training priorities:

There’s a balance of Serving In and Serving Tough that every team has to walk. We see that Serving In is important for us to improve. 21% error is not unheard of for men’s volleyball (VNL champ France missed serves at a higher rate than that), but it’s higher than ideal, especially considering that we had multiple float servers in the lineup. However, Serving Tough is the higher priority for us.

What’s interesting is that the gap between us and opponents in Earned Sideout is higher than the gap between us and opponents in Sideout, which includes errors. This again shows that missing serves, while not ideal, was not the full catalyst. It was being better within the rally.

Summing It Up

So, there was a 9% Sideout gap (73% to 64%) between us and opponents. The stats tell us that this 9% gap breaks down about as follows:

2.0% Offensive underperformance
2.0% Defensive underperformance
2.0% Pass quality
1.8% Serve Tough
1.3% Serve In

Or, in relative terms:

Coaches assess things in different ways when translating priorities to practice planning.

You could say: “Serving and Passing” should be the main priority, because it’s more than half of this total gap that we’re looking to close.

You could also say that “Point Scoring Phase” should be the main priority because Serving + Block/Defense is more than half of the total gap that we’re looking to close.

It’s less important to come up with some mathematical formula that perfectly assigns skill importance to practice time allocation than it is to just have a conceptual model in your head. Each coaching staff runs training a bit differently, and you also have to assess the capabilities of your players to see where the potential improvement is.

But my takeaways from this were that we either need to spend a lot of time investing in the whole Point Scoring phase (Serve/Block/Defense) or else really raise the level of our Serve and Pass game.

More on these concepts in the coming weeks…

1. In beach I actually do include missed serves when I run these sorts of analyses, but that’s a topic for another day.

2. Both xSO and xFB align have about the same gap between us and our opponents.