What is contributing to Julio Rodriguez’s struggles at the plate?

Following two all-star seasons, Julio Rodríguez is midway through 2024 with a disappointing .635 OPS and 7 home runs. According to Stathead on Baseball Reference, that OPS puts Rodríguez at 56^th out of 62 outfielders who have at least 250 PAs this season. In this post, we are going to explore what could be contributing to his rough first half of the season.

If you prefer video walkthroughs, check out this video:

The first thing that jumped out to me was the difference between Rodríguez’s actual SLG and his xSLG – .335 vs .437. (Reminder that xSLG is the expected slugging percentage, and is calculated based on exit velocity, launch angle, and sprint speed, depending on the type of batted ball). We cannot just automatically assume that Rodríguez will start performing better based on his xSLG alone. xSLG only takes into account contact, and Rodríguez is making less contact overall this season (zone contact is down 4% and strikeout rate is up 3%).

We need to dig deeper to understand why his actual stats differ so much from his expected.

Rodríguez is historically much more successful against hard pitches (fastballs) compared to breaking and off-speed pitches. This is not uncommon, but serves as a good starting point to figure out what’s going on.

The table below shows Rodríguez’s performance against all pitch types from RHP during the 2022-2024 seasons. I excluded the changeup, as this is typically a pitch we see against batters of the opposite hand. Green indicates the results are good for the pitcher, with the exception of swing rate, which just indicates Rodriguez’s tendency to swing.

If I was the opposing pitcher, based on this table alone I am avoiding the fastball as much as possible and lean on my breaking and off-speed stuff when facing Rodríguez. The curveball and sliders in particular stand out as effective pitches.

There is a similar takeaway from the same table but vs a LHP:

Curveballs stand out as a weakness, along with a changeup. Note that I removed the splitter, as it had an extremely small sample.

Based on this information, one potential reason for Rodríguez’s down year could be that he is being pitched differently to exploit his weaknesses.

At an overall level, he appears to be pitched very similarly compared to last season:

(Visual is from Baseball Savant)

But if we dig deeper, we can identify differences compared to last year. While each difference may seem minor, adding them up altogether could play a factor in his struggles.

For context into his approach at the plate, Rodríguez has shown over the past two and a half seasons that he tends to be more aggressive than the average hitter in all counts except those with two strikes. (Against RHP, he swings 4% less in 2K counts and against LHP he swings 6% less).

Now that we understand his approach, we can dive into specific changes in pitch mix based on count and pitcher hand:

Vs RHP

• First Pitch: Seeing 7% more breaking pitches and making 18% less contact.
• Counts with Less than 2 Strikes: Seeing 4% more breaking pitches and making 4% less contact.
• Full Count: Seeing 12% more breaking pitches. Missing 10% more and chasing 10% more.
• Hitters Counts (1-0, 2-0, 3-0, 2-1, 3-1): Seeing 6% more breaking pitches. Making more contact, but it’s not coming with ideal results. Let’s compare the contact data from 2023 to 2024:

Compared to 2023, Rodríguez is doing less damage in hitters counts. He is hitting more foul balls, has fewer hard-hit balls, and his launch angle is down.  

Vs LHP:

• Even Counts (0-0, 1-1, 3-2): Seeing breaking and off-speed pitches 8% more and is chasing 12% more.
• Counts with Less than 2 Strikes: Seeing 4% more breaking pitches and missing 6% more.
• Hitters Counts (1-0, 2-0, 3-0, 2-1, 3-1): Seeing the changeup 9% more and is missing 11% more. We see a similar takeaway to his results in hitters counts against right-handed pitchers:

Compared to 2023, Rodríguez is doing significantly less damage in hitter’s counts against left-handed pitchers.

Many of the points listed above are leading to Rodríguez either falling behind in the count more frequently than in years past and/or getting to counts where he can no longer afford to be aggressive and needs to protect. He is being forced to face the pitches he has the most trouble against in the counts where he typically does the most damage.

This appears to be a targeted approach when facing Rodríguez. Even though on an overall level Rodríguez is seeing the same frequency of pitch type, breaking it down by pitcher hand and count exposes seemingly minor changes that are adding up to lead to worse results overall against both right- and left-handed pitchers.

Note: All data in tables is from TruMedia