Luis Arraez and the Art of Batting Average – BAT FLIPS & NERDS

Arguably the most unique hitter in baseball is Luis Arraez. He is what I imagine all players were before Babe Ruth came on the scene. Contact, contact and more contact. Nowadays though, hitting over .310 doesn’t make you a good hitter, let alone a star. Since Arraez is once again in trade rumours, let’s discuss whether he’s a player worth trading for.

There is only one place to start when evaluating Arraez, and likely the reason you are even reading this. How important is Batting Average?

A question that seems so nice at first, is one of the worst questions I’ve ever asked. Mainly, because of how many questions pop up before we can start answering.

Firstly, what baseball statistics are actually important? WAR? OPS? wOBA? I even read an article where ISO was regarded as one of the best stats to evaluate a hitter.

Let’s try and approach this mathematically. To begin, only one statistic matters in baseball and that is wins. So, if we can figure out what has the best correlations to wins, that’s not a bad start!

I’ve decided to take my statistics from 2021 to 2024 and we’ll go over every stat we can find. Got to get my money’s worth out of that FanGraphs membership.

Due to the Rockies and Braves rudely missing a game in 2021, we will use win percentage. This is arguably a better way to present the data regardless. Let’s start with the counting stats; they’ll give us a good idea of what aspects of hitting create wins.

Runs unsurprisingly have the highest correlation of the counting stats. Perhaps, more surprisingly though, is that both home runs and walks have higher correlations than hits. It’s not looking good for Arraez early doors, that’s for sure…

Next, we’ll look at the statistics that have been created over the years. Let’s start with the old-school statistics in the typical order you’d find them.

Due to our earlier results, it is unsurprising that AVG has the weakest correlation. More surprising is the strength of OBP, particularly in being higher than SLG. You Moneyball fans may be shouting at me for that statement though…

Whilst nothing is as strong as runs, OPS introduces us to the idea of a statistic that is better than each one of its parts. Using OBP and SLG together gives us a stronger relationship to wins. Let’s see if the newer stats work just as well at this.

Whilst proving the underwhelming impact of stealing bases and running the bases well, we also found a new winner. All three top stats are based on wOBA. A stat that has for a few years now been hailed as the successor to OPS. It’s not hard to see why either, even if it is only a small improvement.

It’s at this point where you’d expect me to say, ‘But runs have a higher correlation yet again!’. However, I would be lying because I’m hiding a particular stat from you.

That plus sign doesn’t just make reading stats easier; it gives us an even better relationship with wins. This isn’t too much of a shock, adjusting to each individual park is important in weighing up offensive impact. A run in Coors Field doesn’t mean as much as a run in Oracle Park, for example. This is why it even leapfrogs the hits statistic itself to become our best stat.

Now, we finally have our ‘best’ pure-hitting stat and the impact of all stats. Let’s now get back to Arraez and his statistics since 2021 and see his statistics over the past four years.

Firstly, it’s important to point out that 2024 was an obvious down year. Arraez struggled with injury throughout the year, a point many fail to mention. I think this year gives us a really helpful base, especially when showing the impact of AVG on wOBA and wRC+.

The identical wRC+ values in the 2022 and 2023 seasons are a great visualisation of the league-wide offensive boom in 2023. For example, a .369 wOBA in 2022 would have given Arraez a wRC+ of over 140 in 2023. This is a big reason why wRC+ is such a helpful stat and has an impressive correlation to wins. It allows us to judge offensive output based comparatively to the rest of the league. We can even use it to argue that his 2022 season was as impressive as his 2023 season, despite worse general offensive numbers.

When looking for a more consistent relationship for AVG though, we should use wOBA. Not only because it is the base for stats like wRC+. It also stays consistent year on year, regardless of changes around the league. Below are the differences from year to year and tell an interesting story.

The first point is that batting average plays a role in wOBA, but that should be unsurprising given both are based at their core on hits. The more interesting part is that despite both changes in average being near identical, the differences in wOBA are very different.

In particular, Arraez’s 2024 season was historic, for mixed reasons. He had the third-lowest wOBA in MLB history for any player with 400 PAs and averaged at least .310. Bonus points if you guess the two with worse seasons. Essentially, 2024 is the floor for Arraez, as it would be a shock if he were to hit under .310, especially after doing so whilst being injured for a year.

So, whilst batting average is far from the best way to judge a hitter’s contribution, it has far more of a say than most give it credit for. All hitting statistics are based on hits and outs, they just scale them differently depending on what they want to show. Average will always then, provide as a base for any stat you choose.

For guys like Arraez, then, who consistently battle for batting titles, they’ll never be below-average hitters. They can walk 3.6% of the time, have an ISO of 0.078 and still be 9% above league average. Not just based on any stat, but on what we worked out to be the strongest metric in relation to winning games! Maybe those old heads have a point after all…

Featured Image by MLB on X

Article by Alex Williamson. Look out for more analytics-based content from Alex during 2025 and follow him on bluesky @alexwilliamsonmlb.

[Editor’s note: From Alex “The answers are George Maisel 1921 (.310 AVG .317 wOBA) and the one people might get is Felix Fermin 1994 (.317 avg .319 wOBA).” – no, me neither]