Antaeus, the giant of Greek mythology, was unbeatable as long as his feet remained planted on the earth. Hercules defeated him only by lifting him off the ground.
Martín Pérez has spent 2026 staging baseball’s version of the story: He owns a 1.80 ERA at Truist Park and a 4.76 ERA everywhere else.
Appropriate for the comparison, Pérez also keeps the baseball on the ground considerably more often at home.
But this isn’t some sort of mythological phenomenon; It’s a combination of good fortune, legitimately better contact management and one particularly strange problem with left-handed hitters. Let’s talk about it.
Two completely different pitchers
Martín Pérez made two starts in the last week, one good and one bad. In Philadelphia last Saturday, he allowed four runs on seven hits and three walks in just 3⅔ innings.
And then at home on Thursday, he went seven scoreless against Tampa Bay, with three of his four hits coming in the first inning.
The two outings left his road ERA at 4.76, while his home ERA is just 1.80 (and a mere 0.28 across his last six home starts).
It’d be easy to look at these splits and come to the conclusion that Pérez is a different pitcher in Truist Park. I had someone ask on the podcast this week if the Braves should make their October game three starter decision between Pérez and Grant Holmes based on whether the game is on the road or at home.
But the underlying numbers suggest something more…complicated: The home version of Pérez really is better, but the 1.80-ERA version isn’t who he really is.
| Metric | Truist Park | Road |
| ------------- | ----------: | -------: |
| Innings | 75.0 | 56.2 |
| ERA | **1.80** | **4.76** |
| WHIP | 1.04 | 1.52 |
| Opponent AVG | .178 | .278 |
| Opponent wOBA | .240 | .361 |
| xwOBA | .296 | .366 |
| BABIP | **.206** | .306 |
| HR/9 | 0.48 | 1.43 |
| FIP | 3.72 | 4.92 |
| xFIP | 4.30 | 4.53 |
| K-BB% | 6.8% | 8.7% |So, that raises the question: What actually changes when Pérez leaves Atlanta?
It isn’t his command
Pérez struggled against Philly on the road last weekend, walking multiple Phillies in the first inning, so this is the first place I looked.
Nope. He actually throws a larger percentage of pitches in the zone on the road. He’s also getting ahead of more batters away from Truist Park and has a better strikeout-to-walk ratio:
Home K-BB%: 6.8%
Road K-BB%: 8.7%
Home first-pitch strike rate: 59.4%
Road first-pitch strike rate: 61.0%
The road version of Pérez isn’t hurting himself before the ball is put in play. He is getting hurt after.
The contact really DOES change
At home, Pérez gets hitters to chase more frequently, keeps the ball on the ground more reliably, and avoids barrels. On the road, however, hitters both make more contact in general and elevate it more frequently.
| Metric | Home | Road |
| ---------------------- | -----------: | --------: |
| Chase rate | **29.8%** | 24.3% |
| Swinging-strike rate | **9.7%** | 7.7% |
| Contact rate | 78.3% | 81.4% |
| Ground-ball rate | **48.5%** | 41.6% |
| Fly-ball rate | 30.9% | **35.4%** |
| HR/FB | **6.3%** | 14.3% |
| Statcast hard-hit rate | **32.2%** | 42.0% |
| Average exit velocity | **86.0 mph** | 87.9 mph |And this isn’t really a pitch mix thing - Pérez throws roughly four percent more changeups at home, but the sinker and cutter usage are almost identical. Whatever is driving the difference, it isn’t simply Pérez deploying a radically different repertoire at home.
| Pitch | Home usage | Road usage | Home wOBA/xwOBA | Road wOBA/xwOBA |
| --------- | ---------: | ---------: | --------------: | --------------: |
| Sinker | 35.1% | 35.2% | .251/.320 | .380/.394 |
| Changeup | **32.9%** | 28.7% | .186/.253 | .277/.323 |
| Cutter | 21.9% | 21.6% | .292/.329 | .441/.369 |
| Curveball | 6.5% | 8.6% | .203/.229 | .614/.447 |The results still overstate the difference
This is where I want to caution everyone about regression. Pérez has pitched better at home, but he’s not three runs of ERA better at home. When you replace his actual, observed wOBA with the expected outcomes, roughly 40% of this home/road wOBA gap just disappears into thin air.
Home wOBA: .240
Home xwOBA: .296
Road wOBA: .361
Road xwOBA: .366
Home BABIP: .206
Road BABIP: .306
Home strand rate: 85.8%
Road strand rate: 72.9%
Home FIP/xFIP: 3.72/4.30
Road FIP/xFIP: 4.92/4.53
Interestingly, almost all of the regression is on one side. Pérez’s .361 road wOBA is almost perfectly supported by his .366 xwOBA. It’s the absurd .240 home mark that Statcast expects to move substantially toward the middle.
The home and road xwOBA gap is still 70 points, which is significant - the home advantage isn’t a figment of our imagination, cooked up in a fever dream. But it’s not as strong as the results make it appear.
Lefty hitters are still a mystery
The biggest remaining mystery is why left-handers become so much more dangerous to Pérez on the road as compared to in Truist Park. When you compare that delta to the split for righties, you can see that this is a big difference.
| Opponent | Home wOBA/xwOBA | Road wOBA/xwOBA |
| -------------------- | --------------: | --------------: |
| Left-handed hitters | **.216/.286** | **.434/.427** |
| Right-handed hitters | .251/.300 | .333/.342 |So naturally, I did a little poking around.
And I think it’s the sinker.
Remember how we wrote about the other October game three candidate, Grant Holmes, and came to the conclusion that he needed to throw more right-on-right changeups?
Acknowledging that this is a small sample size, it feels like Pérez needs fewer left-on-left sinkers on the road, possibly replacing those pitches with his excellent cambio.
Road changeups to lefties: .148 wOBA/.230 xwOBA.
Road sinkers to lefties: .492/.485.
Home sinkers to lefties: .221/.307
Despite the obvious disparity in performance of the sinker on the road, he still throws approximately 55% sinkers and only 25% changeups to road lefties.
If Atlanta wants to travel the home version of Martín Pérez, the first experiment should be reducing his road sinker usage against lefties and trusting the same-handed changeup that’s already shown itself capable of neutralizing them.
This didn’t start at Truist Park
As you may remember from our deep dive into Atlanta’s home vs road offense, Truist Park has a three-year park factor of exactly 100, so perfectly neutral, in both overall offense and home runs specifically.
But for Martín Pérez, the home park doesn’t matter - he’s better there than on the road, going back the last few years and three different home ballparks.
| Span | Home | Road |
| -------------------- | -------: | -------: |
| 2024 ERA | 3.35 | 6.16 |
| 2025 ERA | 2.35 | 4.97 |
| 2026 ERA | 1.80 | 4.76 |
| **2024–26 combined** | **2.55** | **5.37** |That span includes his time with Pittsburgh, San Diego, Chicago, and Atlanta, and that’s the part that changed how I looked at this.
Three seasons. Four organizations. Multiple home ballparks.
The addresses keep changing. The split doesn’t.
Whatever is happening, it predates Truist Park. That may be where we first noticed it, but it isn’t where Pérez developed it.
Final Thought: October
This was all inspired by a question on the podcast: Should the Braves choose between Pérez and Grant Holmes for a potential Game 3 based on whether that game is at home or on the road?
At least in the Wild Card round, Atlanta currently projects to be at home.
Pérez has given the Braves legitimate reasons to trust him more at Truist Park. But Atlanta shouldn't choose its Game 3 starter based on the address. It should choose the pitcher whose process gives them the best chance to get 27 outs.
Rather, the question between now and Thursday, October 1st (the first time Atlanta might play a game three in the postseason) is if the home process - more chase, more grounders, and heavier changeup use - can travel.
The Braves don’t need to bottle whatever magic Pérez has found in the home cooking of Truist Park. They need to identify which parts of it can survive the road trip.