Navigating Baseball Savant For Vladimir Guerrero Jr's Stat Profile
I spent probably three hours last Tuesday just digging through Baseball Savant's tools looking at Vladimir Guerrero Jr.'s spray charts and exit velocity distributions because someone asked me why his wRC+ dropped from 148 to 121 between 2023 and 2024. The platform has enough data that it can feel overwhelming if you don't know where to point your attention. Here is how I actually approach a Savant deep dive, using VGJr as the case study. The first thing you need to understand is that Baseball Savant's hit tracker and batted ball data are built on StatCast, which uses the Hawk-Eye tracking system. For VGJr, this means every batted ball he has faced since 2019 has an associated exit velocity, launch angle, horizontal and vertical plate approach location, and sprint speed read. The default batting dashboard shows you the summary numbers — the ones everyone cites. Exit velo, hard hit%, barrel%, wOBA, barrels per game. Those are useful. They are also almost never the whole story. I usually start by filtering to the specific season I want to examine, then switching to the Hit Tracker tab. From there, I pull up his spray chart and cross-reference it with the Batted Ball Profile section. The spray chart alone tells you more about a power hitter's deficiencies than any aggregate stat. VGJr's spray chart from his 114 wRC+ season in 2024 showed a noticeable shrinkage in pull-side production — specifically, his hard hit rate on balls pulled to left field dropped from roughly 58% in 2022 to about 44% in 2024. That is not a vague observation. I pulled the individual batted ball data directly from the table view.
The table view is where most people stop, but it is also the most useful part. You can export the raw batted ball events, filter by pitch type, pitch location, count, and situational metrics. When I was trying to figure out what happened with VGJr's strikeout rate rising from 17.6% to 21.3%, I exported all his plate appearances from 2024 and filtered for strikeouts against highfastballs — specifically, sinkers and cutters in the lower half of the zone. His whiff rate on those pitches jumped from 14% in his MVP season to 23% in 2024. That is a nine percentage point swing, and it accounts for a significant portion of the K-rate increase. This is the kind of detail that does not appear in any box score. One caveat that the Savant interface does not make obvious: the default Hot Zones view shows where a hitter has the highest wOBA on contact, but it does not weight for volume. A zone with five balls in play and a .900 wOBA looks just as striking as a zone with two hundred. I always switch to the Plate Zone heat map that shows weighted on-base average per plate appearance, or better yet, I manually filter the batted ball table to only include zones with a minimum of 30 events. Otherwise you are reading noise. Another thing that trips people up is the difference between Expected Average (xAVG) and actual average. VGJr's 2024 xAVG on batted balls was around .278, but his actual average was closer to .265. That gap — called batting average on balls in play or BABIP variance — can be misleading if you interpret it as "he was unlucky." With VGJr specifically, the gap was partly structural. His ground ball rate increased from 38% to 44%, and his fly ball rate decreased. Ground balls have near-zero BABIP value compared to fly balls and line drives. So the xAVG model was penalizing him for hitting the ball on the ground at 95 mph rather than in the air at 97 mph. The expected stats assumed optimal batted ball outcomes for a given launch angle and exit velocity. They did not account for the fact that he was changing his approach and producing more grounders. This is a known limitation of the model, not an error in the data.
When I needed to verify whether VGJr's contact quality was actually declining or if it was purely a platoon effect, I used the Split Stats feature to separate home and away performance, then lefty and righty pitching splits. His split against right-handed pitching dropped from a 132 wRC+ in 2022 to 108 in 2024. That is a 24-point decline. Against lefties, he went from 155 to 138. Both declined, but the righty split was steeper. Savant does not give you a clean statistical test for whether that difference is significant, so I ended up pulling the raw pitch-by-pitch data from the Pitch Feed and running a quick comparison of swing-and-miss rates against fastball velocity. Righties were throwing him harder inside — average four-seamer velocity against him climbed from 95.2 to 96.8 mph over that span, and he was swinging at pitches 2.3 inches higher in the zone than his career average. That is a tangible adjustment, not just a trend line. If you want to go deeper, the Play Finder tool lets you query specific batted ball types across seasons. I used it to compare VGJr's barrel rate on inside pitches versus outside pitches between 2022 and 2024. In 2022, his barrel rate on inside pitches was 12.4%. By 2024, it had dropped to 7.1%. Outside pitches stayed relatively stable at around 9.5%. This is a counter-intuitive finding for a first baseman who traditionally thrives on inner-half power. It suggests the decline was not general contact quality deterioration but a specific vulnerability to starting-velocity increases up and in. Savant will not tell you that conclusion directly. You have to dig through the filters to find it. The one part of Savant that I find genuinely unreliable is the Outs Above Average metric for hitters. It exists, but the sample sizes are small and the methodology is still being refined. I once tried to use it to compare VGJr's 2022 and 2024 defensive positioning contributions, and the numbers flipped back and forth depending on which season filter I applied. The underlying data was the same, but the recalculation that StatCast runs periodically changes historical values. I stopped using OAA for hitters entirely after that. Fielding Runs and UZR from FanGraphs are more stable for that purpose, even if they are not as granular.
Get the Full Details
To actually access all of this, you do not need a paid subscription for the core Savant tools. The hit tracker, spray charts, batted ball profiles, and plate zone maps are free. What costs money is the full StatCast API access if you want to pull the data programmatically, or third-party services like Baseball Prospectus or the FanGraphs API. For manual research, the free tier covers everything most analysts need. I usually just bookmark the player page and cycle through the tabs rather than trying to memorize the navigation. The interface has not changed structurally since I started using it in 2019, so muscle memory works. The main bottleneck with Savant is that it does not give you context for why a stat changed. It gives you the what. The 2024 plunge in VGJr's pull-side hard contact numbers is a fact the platform reports cleanly. But understanding whether it was a mechanical adjustment, a pitch sequencing exploit by opponents, or simply regression to the mean requires you to pull additional layers of data and cross-reference them manually. There is no button that says "explain this drop." You have to construct the explanation from the available pieces. That is where the time goes — not in finding the data, but in connecting it. One more practical note: the Game Log tab is underused. It shows every plate appearance with pitch-level detail, and you can sort by outcome, pitch type, and velocity. When I was investigating whether VGJr's 2024 struggles were concentrated against certain pitchers or diffuse across the league, I exported his full game log and ran a pivot on opponent. The pattern was fairly uniform — no single pitcher was responsible for the decline. It was league-wide, which pointed back to a mechanical or approach change on his end rather than a matchup problem. Savant does not summarize that for you. You have to build the analysis yourself from the raw table.
I keep coming back to the same point: Savant is excellent at surface reporting and adequate at deeper drilling, but it is not a diagnostic tool. It gives you the measurements. You provide the interpretation. For a player like VGJr, where the public narrative often jumps to "he lost his power" or "he is declining," the data actually supports a more specific and less dramatic reading — a shift in contact profile driven by pitch sequencing adjustments from opposing pitchers and a modest increase in ground ball tendency, not a collapse of his underlying skills. The barrel rate is still above league average. The walk rate is stable. The swing rates against pitches in the strike zone have not changed meaningfully. The signal is there if you know which filter to pull.
