Will Jarren Duran Hit a Wall in 2025?

Let’s start off with a graph, shall we? This is straight from Jarren Duran’s player page on FanGraphs. The point I‘m trying to make by leading off with it is that Duran's stardom came out of nowhere.

In his first two stints with the Red Sox in 2021 and 2022, Duran put up negative WAR. He was worse than the average triple-A replacement player. In retrospect, we can say that a 2023 swing change altered the trajectory of his career, but Duran hit a combined .219 over his first 91 games. His 2023 breakout was a real surprise, fueled by a completely unsustainable .381 batting average on balls in play. But instead of coming back to earth, Duran put up 6.7 fWAR in 2024. He was one of the best players in the game.

As is their wont, all the projection systems are buying roughly half of Duran’s breakout, projecting him for between three and four wins in 2024. Amrit Brown broke this down a few weeks ago, but to be clear, those are still good projections; a four-win player is an All-Star. All the same, Duran has spent the past two seasons blowing the projections out of the water. Let’s dig a bit deeper and look for reasons to either believe or disbelieve in the sustainability of his brilliant 2024 campaign. The question we're asking is a tough one: What is Duran's true talent level? The stakes here couldn’t be higher. The Red Sox have added to their starting rotation during the offseason, but the bullpen and lineup are worse. Moreover, the starting rotation overperformed expectations, and we should probably expect the returning starters to regress some. If Duran returns to his previous form as a good player rather than an MVP candidate, Boton’s playoff chances look a whole lot dimmer.

Let’s start with defense and baserunning, as they played big roles in Duran’s 2024 explosion. Duran has always possessed excellent speed, and he’s nearly impossible to double up. Even when he was putting up negative WAR in 2021 and 2022, his baserunning graded out as excellent. Duran is now entering his age-28 season, but with a spring speed of 29.6 feet per second, he was one of the fastest players in the game last season. Even if Father Time slows him down a little, we should expect him to keep putting up gaudy baserunning numbers.

The defense is a bit trickier. As late as 2021, scouting reports indicated that Duran was uncomfortable in center field, and advanced metrics like Defensive Runs Saved and Fielding Run Value backed that up. Duran put up negative marks in both metrics in each season from 2021 to 2023. Then, in 2024, everything seemed to click. Duran’s 23 DRS were the second-best in all of baseball, and his 12 FRV were tied for 12th. I am willing to buy that Duran’s defense will remain good. He’ll still have good speed, and his jumps grade out well according to Statcast. However, he’s definitely due for some regression here. Duran led all outfielders with 12 assists in 2024, and outfield assists are particularly fluky. Duran has a great arm, but he came into the 2024 season with two career assists. The odds that he ends up in double digits again are vanishingly small. We should definitely expect his defense to take a real step back.

With that out of the way, it’s time to turn to the bat. Let’s start once again with BABIP. After running an absurd .381 BABIP in 2023, Duran dropped to .345 in 2024. That’s a big drop, but it was still the eighth-highest in all of baseball. We should expect Duran to run high BABIPs because he’s got great speed and his swing seems particularly well-suited to hitter-friendly Fenway Park. However, you just can’t expect somebody to repeat .345 BABIP. It happens for several batters each season, but those are the outliers. According to the projection system Steamer, literally no one is expected to run a .345 BABIP in 2025. We just should not bank on Duran doing that again.

On the other hand, Duran’s underlying numbers really did show some signs of improvement in 2024. He was much more patient, knocking two percentage points off his chase rate, a big improvement that took him from the bottom third of the league to right around average. As a result, he ran a career-high 7.3% walk rate and a career-low 21.8% strikeout rate. Those aren’t fantastic numbers, but they push Duran toward the league average. You could argue that Duran was too patient – he also swung less often at pitches inside the zone, which isn’t a recipe for success – but I would disagree. According to Statcast, 54% of the balls Duran put into play came on pitches over the heart of the plate, up from 43% in 2023. That’s a huge jump, and swinging at better pitches allowed him to add nearly a full mile per hour to his average exit velocity while nearly doubling his barrel rate. Those kinds of plate discipline gains tend to be sticky year-over-year, which is encouraging.

When we put all that together, the numbers aren’t necessarily encouraging. We should expect Duran to remain a great baserunner while both his offense and defense step back some. There’s also the matter of health. Duran missed only two games in 2024, after a suspension for using a homophobic slur. He’s not particularly young, and he plays extremely hard, so we definitely shouldn’t take it for granted that he’ll stay completely health yet again. Even after his improvement in 2024, Duran’s plate discipline grades out as right around average. Because he hits the ball hard, beats out tons of hits, and takes the extra base, that makes him an All-Star-caliber player. However, it also means that a bunch of things need to break right in order for him to approach the six-win form that he put up in 2024. It’s not impossible, but we really shouldn’t expect it to happen again.