Santander and the mystery of BABIP – BAT FLIPS & NERDS

After an exceptional 2024, Anthony Santander has secured a five-year $92.5 million contract for the Blue Jays. Those in Toronto will be hoping for a repeat of 2024. The All-Star hit 44 home runs in arguably the best season of his career.

Perhaps more impressively, he achieved all of this with the lowest BABIP in MLB. Whilst the Blue Jays will be hoping for a similar level of production to last year, Santander’s season was filled with many oddities, which begs the question, what really happened last year?

Let’s start with the obvious outlier, his BABIP. Just .225 in 2024, it was nearly 25% below the league average of .295.

Let’s clear something up first though, BABIP is in no way just a luck-based statistic. An old but gold article by Steve Staude proves that BABIP has a stronger year-on-year correlation than expected of .370 (bear in mind a complete luck-based stat would have a year-on-year correlation of 0).

It also kindly points us to the main influence behind BABIP: launch angle. The table below takes numbers from EVanalytics and shows the correlations to a range of launch angle statistics. I’ve also included BABIP itself and sprint speed for comparison.

Now you won’t be surprised at what I am going to tell you next. Santander has the second-highest average launch angle of 22.7 degrees and the third-highest pop-up rate at 18.2%. The other two who round out the top three in both categories are Daulton Varsho who hit .214 and Isaac Paredes who hit .238, so Santander’s .235 looks to be fair enough then?

Well, not necessarily. Whilst I stated luck wasn’t the only driving force, it certainly plays its part in BABIP. For example, Varsho and Parades had BABIPs of .262 and .259, respectively, a weirdly long way away from Santander’s .225.

Luckily, expected statistics are there for us to get a feel for how lucky a player has been. First, let me prove to you that they do indeed show luck better. I collected the actual and expected batting averages of all 84 hitters who were qualified in both 2023 and 2024. Then, by plotting the difference between the two numbers for each year on the graph below, we get a correlation of 0.096. That’s fairly close to being independent!

Unbelievably, Santander actually outperformed his xBA! His average of .235 was higher than the expected figure of .228. It is worth mentioning both Parades and Varsho outperformed their xBA by larger margins. However, it is becoming clear that Santander may actually have deserved his last-place BABIP. To prove that though, we will have to find an xBABIP.

We will use simple Statcast xBABIP despite better options being available. The only difference in calculations to pure BABIP is using xBA mulitplied by ABs to replicate hits. Other options have far more added into the calculations but are more statistically significant as a result.

As always, let’s check our new statistic is fit to use. There must be a strong correlation between xBABIP and BABIP in the same year in order for us to use it confidently. Whilst less important, we will also see their uses as predictors for each other. Data was once again collected from 2023 and 2024.

In fact, not only is xBABIP incredibly descriptive of BABIP, it is the best predictor of BABIP we have found so far too! It’s worth also pointing out xBABIP year-on-year correlation works out as 0.514, so is far more consistent year-on-year than BABIP is.

Next, let’s use the same strategy as earlier to prove that the difference between BABIP and xBABIP is mostly luck. The result gives us a correlation of 0.114, higher than for BA but still small enough to deem fairly insignificant. Especially with our small sample size.

Anthony Santander had a calculated xBABIP of 0.220 in 2024, which is below his actual BABIP of 0.225. Given his xBA, this shouldn’t surprise you. What may surprise you though, is that this figure is the league’s lowest yet again. Varsho had a xBA of just 0.186 and still had a higher xBABIP of 0.222. How does that work? I think it’s time to talk about his home runs.

Santander’s 44 home runs put him third in MLB this last season. An incredible achievement for a guy whose next best season had just 33.

Not only that, but he had the 15th-best slugging of 0.506 and fourth-best isolated power of anyone in baseball with 0.271. Expected stats can have their say in power, too, though. Incredibly, his xSLG of only .445 puts him in 49th place, and his xISO of .218 puts him down to 23rd. Despite the still impressive numbers, they put him in the conversations with a player like Shea Langeliers. Who, despite having his best season offensively, hasn’t seem to had many plaudits.

How is this possible then if he hit 44 home runs? Well, there appears to be luck involved with them too. Adjusted to the parks he played in 2024, his xHR was ‘only’ 36.6. Even if you take into account the fact he plays the majority of his games at a pitcher-friendly park, his xHR only becomes 38.6. In fact, had he played 162 games in the same stadium, only two would have seen him hit 44 home runs: Great American Ball Park (48) and Citizens Bank Park (45). No other stadium was above 40.

We could continue to go into a lot more detail on Santander, for good and for bad. For example, he struggled immensely against the fastball. A 13-run value against the pitch in 2023 became -6 in 2024. However, he barreled the ball 1.5% more than he did in 2023. From 10.2% to 11.7%, plus a 93rd percentile max EV of 114.4 mph.

Ultimately, though, it’s important to realise that whilst every little stat plays a part in defining a player. We must not forget the importance of true results. Toronto has just signed a guy who hasn’t slugged under .450 in his three qualified seasons, in that time hitting 105 home runs and collecting 8.2 fWAR. The Blue Jays added some much-needed power to their lineup. Perhaps just not as much as we felt at first glance.

Article by Alex Williamson. Look out for more analytics-based content from Alex during 2025.

Featured image of Anthony Santander by Scott Taetsch/Getty Images