It’s Hip To Be Squared

If you want to get a hit, trying to square up the ball is a great place to start. But not all squared up hits are created equal. Squaring up your grounders and line drives will likely help your batting average, but won’t do much in the home run department. Squaring up your flyballs, especially at the ideal launch angle, should help get the ball out of the yard.

If you look at the surface level Savant lollipops, you will see a “Squared-Up%” metric, which is represented on FanGraphs by “SqUpCon%”. This describes a batted ball event where at least 80% of the possible exit velocity on a pitch was obtained, given the swing and pitch characteristics, which typically means a ball that was hit on the sweet spot of the bat, according to Statcast.

As explored by Fangraphs’ Davy Andrews, even before we look at the launch angle of a squared up ball, we should acknowledge that not all of these swings result in a ball that’s hit even remotely hard, because a ridiculously slow swing that hits the ball on the barrel can still technically be squared up by the Statcast definition. But for the most part, hitters are swinging relatively hard. And we have ways to see just how fast they swing and how often they unleash their fast swings now, thanks again to Statcast. 

With all of this in mind, check out the Fangraphs Squared-Up Explorer. This tool helps you see how often a hitter is squaring up the ball at different launch angles, highlighting the ideal launch angle for home runs and visualizing a given hitter’s profile compared to league average. 

Using this tool, you can compare a given hitter’s profile against other hitters and during different periods of time. You can compare Gunnar Henderson’s hot start in 2024 to his 2025 and to his start to this season, as I did last week. 

Today, I’ll run through a few examples that demonstrate the possible ways to use the Squared-Up Explorer and try to show you that you can and should use this tool yourself as a starting point for analyzing hitters, whether it be struggling bats you may want to cut or hot streak hitters you’re looking for an excuse to believe in. For the hitters I look into, I’ll provide some recommendations, but really want to invite you to use this exceptionally user-friendly tool yourself. 

Let’s start with a particularly frustrating hitter, Fernando Tatis Jr. 

He has yet to hit a home run. Preseason projections expected him to hit anywhere between 27 and 31 long balls, yet here we are at the tail end of May, and he sits homerless. 

Mike Podhorzer summed up this perplexing start to the season well a few weeks back:

[Tatis] still hasn’t homered through 193 PAs, continues to underperform his xwOBA rather significantly, and sports just a 5.7% FB Pull%, compared to his career average of 22.7% and league average of 26.2%. He’s still hitting the ball as hard as always, but striking out a bit more and posting a career low FB%.

I honestly don’t know what could possibly cause the putrid FB Pull%. His BatSpd is actually up from the last two seasons. His FastSw% is up too. What on Earth is going on?! You have to assume he’ll suddenly figure it out, but man, an explanation would be cool. 

Enter the Fangraphs Squared-Up Explorer tool. We’ll use it to answer Mike’s underlying question. The premise is that Tatis Jr. has done enough in the past to be considered a proven commodity, albeit one who is acting differently and putting up poor results to start the season. 

Besides pulling the ball in the air less, could he be squaring the ball up less, and at launch angles that are less than ideal for hitting home runs? Given that his xBA and xSLG are both far below his career norms, and that he’s underperforming his expected stats despite a 54.5% hard hit rate, which puts him in the 97th percentile amongst qualifiers this season, this seems likely. Let’s find out. 

The Squared-Up Explorer allows you to compare a player’s performance against his own across custom time periods. For Tatis, he has put up consistent numbers in each of the last three seasons since his outlier 2022. Between 2023 and 2025, the young outfielder (and now second baseman) has averaged nearly 24 home runs with a .266 AVG and .459 SLG, with little variation from season to season. We’ll take advantage of that relative consistency over a large sample size and compare his slow start against the aforementioned three year period.

Here’s how this input looks in the tool. 

Here are some things to keep in mind when reviewing the visualization. For Tatis, the story this season has been his lack of home runs, despite hitting the ball hard. To try and answer why this may be, despite a history of hitting home runs, we will want to compare how often he is hitting the ball in the air, especially within the range of launch angles that is ideal for hitting home runs (shaded in red in the graphic) and how often he is squaring up his flyballs compared to recent years.  

The gold dots represent the past three seasons, while the blue represents his cold start this season. The size of the dots shows how frequently a given type of batted ball (y-axis) is being squared up (x-axis). Naturally, the higher launch angles are found as you move up the y-axis. 

Notice the gap in Squared-Up Rate between the blue and gold dots. Tatis seems to be hitting most of his flyballs within the ideal launch angle band for home runs, just as he did over the last three seasons, but he isn’t squaring those balls up nearly as often. This gap is shown in clear terms in the “Stats Comparison” table that running the Squared-Up Explorer generates, which is pictured below. The table splits each time period and each player (if different) for direct comparison, supplementing the visual and adding bat speed and hard hit rate.  

When we plugged Tatis into the Squared-Up Explorer, we were seeking to answer two questions: how often he is hitting the ball in the air, especially within the range of launch angles that is ideal for hitting home runs and how often he is squaring up his flyballs compared to recent years.  

The visualization clearly showed that he is not hitting the ball in the air quite as often, though the gap is not especially signifcant. The more notable gap is that he is squaring up his flyballs less often. Thus, despite swinging harder and hitting the ball harder, he has yet to launch a home run.

You could interpret this as a clear sign that Tatis is not likely to regress to his previous power outputs without making a change. Your next question could then be, has he made any changes recently that show he’s turning things around?

Splitting Tatis’s 2026 by month, looking at his results in March/April compared to thus far in May, we would be able to see if there’s any evidence that this could be the case. Maybe he started particularly cold but has warmed up with the weather?

Unfortunately for those of you who roster him, the turnaround does not seem imminent. 

As the comparison chart illustrates, Tatis actually is hitting more groundballs in May than he did through April, hitting the ball hard much less, and hitting fewer flyballs, which are being squared up far less than they were early on. Yikes. 

So, clearly you should not be buying low on Tatis. Or at least you should be clear-eyed about his change in abilities if you do. 

That was an example of how to use this tool to confirm if a hitter who has struggled is really looking different under the hood compared to a past baseline of success.

In Rafael Devers, we find an example of a player who had been struggling and is now seemingly heating back up. Is there a way to see if the batted balls are drastically different now than they were earlier in the year?

Devers, who began May with hits in seven games in a row, started the season (blue dots) with frequent groundballs and line drives, but was not squaring up balls hit in the air. Since the calendar flipped to May (gold), the Giants’ slugger has traded some squsred up grounders for squared up fly balls, hit within the ideal launch angle band far more frequently. Seems like a quick confirmation of a hitter returning to form. 

And could you use this tool to identify a potential breakout, confirming a change in batted balls that goes beyond simply pulling more balls in the air or running a higher BABIP? Let’s use Jake Bauers. At the very least a startable player in deep and daily lineup formats this season, the lefty first baseman has seen a run of success that is far ahead of his career .211/.307/.365 slash coming into the year. His .285/.354/.481 slash and 7 home runs are backed up by gains in his bat speed, hard hit rate, and squared-up rate on flyballs, including those that lead to home runs. 

And what about a hitter who struggled mightily last season, until a late surge. If they have started hot this season, maybe you’ll want to see if they have carried on a change that helped them regain some relevance at the end of last year.

Christian Walker fits that bill. After limping through his first spring in Houston last season, the veteran slugger hit over .300 in June before smacking 8 home runs in July, en route to posting a final line that included 27 home runs and 88 RBI. As a veteran who some remembered struggling, his ADP fell dramatically this spring. Now, he’s been a resurgent partner for Yordan Alvarez and the otherwise struggling Astros, hitting .265 with 14 home runs. Since last summer, has he looked like the hitter he was before his slump?

In this case, the blue represents his cold streak, the gold his stretch since last summer, and the pink his baseline from the 2023 and 2024 seasons combined. And for Walker, he clearly is back to squaring up flyballs at rates more like, and even better than, his career norms.

There are so many hitters, from the surging to the slumping, that could be dug into using this tool. I hope you join me and dive in!