How 'aggressive discipline' makes Seager elite

You might be tempted to call Corey Seager a free-swinger. A hacker. But he wouldn't be the superstar hitter he is if that were completely true.

When the Rangers play, you'll often hear the announcers talk about how aggressive Seager is, or how much he loves to jump on the first pitch. He is, and he does. Seager swings 55% of the time, and over half his plate appearances start with him taking a rip.

And yet … He's also disciplined. That seems paradoxical. We tend to associate plate discipline with not swinging, with laying off bad pitches. But that's being selective, and it's only half the battle. Plate discipline is about attacking the right pitches and laying off the bad ones. Seager is exceptional at that combination.

The Rangers enter the American League Championship Series as the most disciplined team in baseball. They chase fewer pitches than any team in the Majors -- but they also swing at pitches in the strike zone at one of the highest rates in the Majors.

Seager, the pillar of Texas' deep lineup, exemplifies that approach. And he's even more locked in in the postseason -- he's batting .429 with a 1.537 OPS and 11 walks to only two strikeouts. He's the type of hitter who can have a historic five-walk game one day, and unload a rocket home run the next.

"I mean, I think we all know I like to swing," Seager said after drawing those five walks. "So I probably would not have bet that I would be the person to do that. But this team's really good at staying within themselves. We've talked all year about passing the baton, and I feel like we've done that extremely well this postseason."

Call it "aggressive discipline." Here's how Seager is leading the way at the plate for the Rangers.

The coolest part about Seager's approach as a hitter is how, as you move from the center of the strike zone to the far reaches outside it, he goes from one of the most aggressive hitters in the Majors to one who's actually discerning about not swinging at balls.

Statcast divides the hitting zone into five regions:

• Meatballs: True middle-middle pitches in the strike zone
• Heart: Pitches more than a baseball's width inside the strike zone
• Edges: Pitches within one baseball's width of the strike zone borders
• Chase: Pitches more than a baseball's width out of the strike zone
• Waste: Extreme out-of-zone pitches

Here's how Seager's swing rate changes, region by region. For pitches on the edges, we're dividing them into in-zone edge pitches and out-of-zone edge pitches, because there's a fine line between "strike" and "ball" there and you want a hitter who knows the difference.

Seager's swing % by zone, 2023 regular season
Meatball: 95.9%
Heart: 90.8%
Edges -- In-Zone: 76.0%
Edges -- Out-Of-Zone: 47.1%
Chase: 21.0%
Waste: 2.0%

Now here's how you know he's even more locked in for the playoffs:

Seager's swing % by zone, 2023 postseason
Meatball: 100%
Heart: 93.8%
Edges -- In-Zone : 73.3%
Edges -- Out-Of-Zone: 36.0%
Chase: 14.3%
Waste: 0%

His aggressiveness in the strike zone and discipline in not chasing is even more pronounced than it was in the regular season. Seager has swung at 15 of the 16 pitches he's seen in the heart of the zone, including all seven that have been right down the middle, and he's only gone after five of the 42 chase and waste pitches he's seen.

"He's being really stubborn with pitches he likes to swing at," Seager's teammate Mitch Garver said during the Division Series.

Let's focus on two of those zones: Heart and Chase. Pitches in the heart of the zone are hittable pitches, the ones you want to attack; pitches in the chase zone are the ones it requires skill to lay off of (basically all big league hitters very rarely swing at waste pitches).

Seager, between the regular season and postseason combined, has swung at 90.9% of pitches in the heart of the strike zone -- the highest rate of any MLB regular -- but only 20.5% of pitches he's seen in the chase region.

Swinging at over nine out of every 10 pitches in the heart of the zone vs. barely two out of every 10 in the chase zone is a massive difference. In fact, the gap between Seager's Heart swing rate and Chase swing rate is the biggest of any hitter in the Majors this year.

Biggest gap in Heart vs. Chase swing rate, 2023
Regular and postseason combined

1. Corey Seager: 70.4% -- 90.9% Heart | 20.5% Chase
2. Kyle Tucker: 68.5% -- 83% Heart | 14.5% Chase
3. J.D. Davis: 67.7% -- 86.7% Heart | 19% Chase
4. Marcus Semien: 66.8% -- 81.4% Heart | 14.6% Chase
5. George Springer: 66.3% -- 81.7% Heart | 15.4% Chase
6. Freddie Freeman: 64.9% -- 85.9% Heart | 21% Chase
7. Matt Chapman: 63.8% -- 77% Heart | 13.2% Chase
8. Aaron Judge: 63.5% -- 77.1% Heart | 13.6% Chase
9. Ronald Acuña Jr.: 63.3% -- 79.8% Heart | 16.5% Chase
10. Edouard Julien: 63.2% -- 71% Heart | 7.8% Chase

MLB avg. swing rates for 2023: 72.8% Heart | 23.3% Chase

Seager swings 4 1/2 times more often at the most hittable pitches than he does at the least hittable pitches. Take him at his word when he says that he loves to swing -- but he doesn't love to swing at everything.

He's such a threat to do damage at any time because he hacks when the time is right. If you come too brazenly into the hitting zone, he'll do that right away. But you can't just throw him bad pitches and think he'll get himself out, either. He won't.

Seager's aggressive discipline is no paradox. It's just the mark of an elite hitter -- maybe the best hitter in the 2023 postseason.