Huntering the Most Dangerous Game

Reggie Hildred-USA TODAY Sports

The Washington Nationals are 10-11 coming out of last weekend’s 2019 World Series rematch with Houston, which is a mild surprise. I thought they’d finish way off the back of the pack in the NL East, and based on how the Marlins have faceplanted out of the gate, it seems I owe the Nationals an apology. And this is not a case of a mediocre team coming off the blocks hot by beating up on a bunch of glorified Triple-A opposition. Washington has played some pretty solid competition, with a series win against the Dodgers on the road sprinkled in there, too.

When a team exceeds expectations like this, there’s usually a good bullpen involved. Sure enough, Nats closer Kyle Finnegan has been strong (though his underlying peripherals are concerning), but the team’s real standout has been Hunter Harvey. Harvey made his first appearance in Washington’s second game of the season, entering in the eighth inning of a tie game in Cincinnati. It didn’t go well; he allowed two runs in one inning of work. But the offense bailed him out, tagging no less a reliever than Alexis Díaz for three runs in the top of the ninth. So despite a rough day at the office, Harvey escaped with a win.

And perhaps as a token of gratitude, Harvey has been basically untouchable since. In his past nine outings, totaling 10 innings, Harvey has struck out 17 batters, walked none, and allowed just a solitary run. He’s recorded holds in seven of those appearances and a positive WPA in all nine. His FIP in that span is below zero.

Far out.

Or not far out, actually. In his second appearance of 2024, Jeimer Candelario hit a ball to the gap that was within about a foot either way of being a home run or an out; it split the difference and bounced off Lane Thomas’ glove for a double. That’s the longest batted ball Harvey has allowed all year — nothing else has had an estimated distance of more than 303 feet.

Harvey was a first-round pick of the Orioles in 2013, and is arguably still most famous as one of the last victims of the 30-year period in which being an Orioles pitching prospect was — as omens go — somewhat less encouraging than having a blind man named Pew show up at your hotel room and hand you the black spot.

The North Carolina native was a consensus top-100 prospect, but his early professional career was derailed by injuries both mundane — UCL reconstruction — and exotic — sports hernia, oblique strain, shoulder discomfort, fibula strain. (The fibula’s a bone. I didn’t know you could even strain those.)

A winter of floating on the great and mysterious waiver wire currents brought Harvey down to Washington, where he’s been a very good reliever for two seasons and change now: Since the start of 2022, Harvey has made 105 appearances with an ERA of 2.68.

But we’ve seen nothing like this.

It should surprise no one, given that I’ve already mentioned Harvey’s negative FIP since April 1, that he leads all relievers in WAR this season. It’s early, yes, but there are indications that Harvey has improved his already-impressive baseline of performance from previous seasons.

The first change from 2023 is in pitch mix. Last year, Harvey had something resembling a starting pitcher’s repertoire, despite having been a one-inning reliever basically since mid-2019. Harvey threw his four-seamer a majority of the time, along with a splitter and not one but two breaking balls. In previous seasons, Harvey had mostly gone fastball-splitter-curveball, but in 2023 he threw 13.9% sliders, almost exclusively right-on-right.

And he had success; opponents went 2-for-23, both singles, off Harvey’s slider. But this year, Harvey has cut his breaking ball usage. He’s still throwing both breakers, but his total breaking ball percentage (9.7) is lower than his slider usage alone last year.

So what’s he doing instead? Fastballs 65.1% of the time, splitters a career-high 25.3% of the time, and more of them than ever to same-handed batters. He’s thrown 16 right-on-right splitters so far this season, resulting in seven swings, four whiffs, and two groundball outs. His splitter has arguably been more effective against righties than lefties, who have hit a couple hard liners off it — including the Nick Martini double on March 30 that accounts for two-thirds of Harvey’s earned runs this year — but comparing its effectiveness by batter handedness would be *splitting* hairs.

Considering Harvey as mostly a fastball-splitter guy, now on the rare occasions he throws a breaking pitch it comes as a walloping shock to hitters who are expecting something with arm-side movement. It’s ironic that Harvey has improved by de-emphasizing his best pitch from last year, but so far it’s working.

But the change in pitch mix is probably not the most important tweak Harvey’s made.

If you’ve ever played Little League, coached Little League, had a child who played Little League, or been close friends with someone who’s played Little League, you know that every 12-year-old pitcher has to be browbeaten into throwing strikes. There’s no use in trying to paint the corners at that age; 99% of middle schoolers just don’t have that skill in their toolkit yet. Just get it over the plate — ideally with some velocity, or with movement if you can throw a breaking ball or a changeup at that age — and if the batter hits it, we’ll figure things out later.

A very small percentage of those walk-happy tweens will grow up to be major league pitchers, and when they do, the art is a little more complex. You don’t want to throw too many strikes, or else hitters will jump all over you. At least, that’s mostly the case. Because Harvey, at this early juncture, is making it look simple.

Everybody’s Got a Hunter Harvey
Stat O-Swing% Z-Swing% Swing% Z-Contact% Zone%
Value 39.2 73.2 59.7 73.2 60.2
Rank* 6th 12th 2nd 6th 5th
*Through 4/21, minimum 10 IP (245 pitchers)

To summarize: Harvey is working in the zone more than 98% of pitchers in the league. That goes a long way toward explaining how this guy hasn’t walked anyone in more than three weeks. Again, that usually comes with the tradeoff of getting hit harder, but Harvey is getting away with it because he’s missing more bats in the strike zone than 98% of the pitchers in the league.

Harvey’s whiff rates outside the zone are pretty pedestrian, as are his batted-ball numbers. But even on those rare occasions when Harvey deigns to venture off the plate, opponents are chasing almost 40% of the time — again, among the very best ratios in baseball. And he’s not having to resort to throwing breaking balls to do it; Harvey’s fastball and splitter are both in the 94th percentile for chase rate among all pitch types.

To say that’s huge would be an understatement. Harvey’s in-zone rate is up almost six percentage points from last year, and his O-Swing% is up more than 10 points. It’s hard not to be an elite pitcher with this many strikes on the board, either from whiffs or called strikes; the only other pitcher with a swing rate as high as Harvey’s this year is Jared Jones, whose performance this season has caused no end of excited ink spillage.

Going forward, I’m interested in two things: Whether Harvey can continue to post anything like these plate discipline numbers, and how real his groundball rate is.

Harvey had always thrown a splitter in the majors, but after joining the Nationals in 2022, he tweaked it and dropped about 600 rpm from the pitch. Now, I love a low-spin splitter an indecent amount, but this has not traditionally resulted in a ton of weak grounders for Harvey. His GB/FB ratio is usually within a couple tenths of 1.00, and even now, he’s getting the most grounders on his fastball and the highest percentage of grounders from his curve. So with the caveat that this is a minuscule sample size — just 26 balls in play total — it’s worth noting that Harvey has a GB/FB ratio of 5.00 right now. Among pitchers with at least 10 innings pitched, that’s second in the league behind only the now-injured Framber Valdez. (Perhaps there’s a truism similar to the one where stats are real once Mike Trout leads the league in WAR: Batted ball numbers are real when Framber leads the league in groundball rate.)

In short, let’s not get out over our skis over 10 great innings from a veteran setup man on a fourth-place team. However, Harvey is throwing a ton of strikes, literally not walking anyone, missing bats in the zone, getting batters to chase outside the zone, and when he does give up contact it’s a combination of soft line drives and negative-launch angle grounders.

What else would you want from a pitcher?

Michael is a writer at FanGraphs. Previously, he was a staff writer at The Ringer and D1Baseball, and his work has appeared at Grantland, Baseball Prospectus, The Atlantic,, and various ill-remembered Phillies blogs. Follow him on Twitter, if you must, @MichaelBaumann.

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Petey Bienelmember
1 month ago

Are you a GM of a team that thinks it will be a contender? Do you have a need for a high leverage bullpen? Does the bonus of another year of team control give you extra 2% chills? Will your fans be OK with Charlie Daniels blaring when your bullpen ace enters? Call Mike Rizzo and make an offer. You don’t even have to explain why you didn’t last year. Mike’s making deals!