PLAYER REVIEW: DJ HERZ
Age on Opening Day 2025: 24
How acquired: Traded with Kevin Made from Cubs for Jeimer Candelario, July 2023
MLB service time: 99 days
2024 salary: $740,000
Contract status: Under club control, arbitration-eligible in 2028, free agent in 2031
2024 stats: 4-9, 4.16 ERA, 19 G, 19 GS, 88.2 IP, 76 H, 45 R, 41 ER, 11 HR, 36 BB, 106 SO, 3 HBP, 1.263 WHIP, 97 ERA+, 3.71 FIP, 0.7 bWAR, 1.7 fWAR
Quotable: “I’m proud of myself getting through this first one. It was really good. I’m just thankful to get through the season healthy and have another full season down.” – DJ Herz
2024 analysis: The Nationals obviously were intrigued all along by DJ Herz, who they sought from the Cubs in last year’s Jeimer Candelario trade. But they knew the left-hander, while talented, was quite raw and typically battled command problems. They saw evidence of that in spring training and early in the season at Triple-A, where he issued a staggering 24 walks in his first 20 2/3 innings.
Herz worked with the Rochester coaching staff on fixing his “direction” toward the plate, and he saw immediate results: three straight excellent starts with only five total walks issued. And when Trevor Williams’ flexor strain created an opening in the big league rotation, the Nats decided to give the kid a shot.
Herz’s first two major league starts, unsurprisingly, were a bit erratic. His third start, however, was brilliant: six scoreless innings of one-hit ball with 13 strikeouts and zero walks, a performance that drew comparisons to Stephen Strasburg’s big league debut nearly a decade and a half earlier. He had another 10-strikeout, zero-walk outing a few weeks later but remained inconsistent to the point his ERA stood at 5.17 heading into the All-Star break.
The Nats optioned Herz back to Triple-A around the break, not so much for performance reasons but because they wanted to give his arm a break, recognizing his workload would need to be limited in the second half. He returned in late-July and went on a sustained run of success, delivering a 2.76 ERA over 10 starts while averaging more than a strikeout per inning to close out an impressive rookie campaign.
2025 outlook: The Nationals figured they’d get a look at Herz sometime this season. They didn’t necessarily think they’d get 19 big league starts out of him and watch him succeed as much as he did. Which suddenly puts him right in the middle of their 2025 rotation plans.
Herz isn’t a finished product, of course. There’s still plenty of room for improvement. His 9.4 percent walk rate, while better than it was in the minors, remains high for a major leaguer. And with 4.15 pitches thrown on average per batter, his pitch count tended to balloon and prevent him from going deep in games. (Though the team also intentionally let him exceed 93 pitches only once in 19 starts to try to manage his workload.)
But there’s no denying Herz has the stuff to overpower hitters at any level when he commands it. His 93.5 mph fastball doesn’t sound all that imposing, but it has legitimate life on it and can be thrown up in the zone with regular success. And his changeup, which he throws with a “Vulcan” grip, plays exceptionally well off the fastball and drops to the bottom of the zone to keep hitters honest. His slider could still use some refining, ensuring he has faith in three quality pitches, a necessity to face a big league lineup three times.
Where does that leave Herz in the Nationals’ current and future plans? There are probably more variables with him than anyone of their other young starters. There’s a scenario in which it all comes together for him and he ascends into a prominent role near the top of the rotation. There’s a scenario in which he’s just too erratic to be counted upon like that and he instead settles into a back-of-the-rotation role, with the hope that he spins some gems scattered around his duds. And there’s a scenario in which he doesn’t succeed with enough regularity and he gets bypassed by other up-and-coming arms.
But at this point, there’s certainly enough to like about Herz to want to see more of him in 2025.