Kristian Campbell’s Rise Is a Player Development Win for the Red Sox

In his Sunday Notes column at FanGraphs, David Laurila published an interview with Kristian Campbell conducted at this week’s rookie development camp. David speaks to many Red Sox players and coaches, and I've written before about how vital his interviews are, especially for Red Sox fans. This week’s entry was no exception, and it highlighted the way that Boston's player development department is helping hitters become the best versions of themselves.

Campbell has changed his swing since being drafted out of Georgia Tech, and when asked about it, he answered simply, “It’s been all about pat path.” He went on, “Instead of being flat, or straight down, I’m trying to hit the ball at a good angle. That’s what I lacked coming into pro baseball, hitting the ball in the air. I never really hit for power before last year.”

The numbers bear that out. We don’t have batted ball stats for Campbell’s 2023 season at Georgia Tech, but in his 22 games in the Red Sox organization, he ran a 50% groundball rate. That number dropped to 43% in 2024. Not at all coincidentally, Campbell’s isolated slugging percentage rose from .162 to .228. Campbell has always had excellent bat-to-ball skills, and thanks to a subtle adjustment to his posture and his hand placement, he’s hitting for power and he’s one of the top prospects in all of baseball. 

I realize that not everyone is on board with the launch angle revolution. Teaching players to hit the ball in the air, emphasizing power over contact, doesn’t sit well with some. However, I want to show you a very simple graph. All I did was take each MLB team’s fly ball rate and wRC+ from 2013 to 2024. The correlation is extremely strong. If you’re a math person, r = .72. If you’re not a math person, just look at that trendline. The Red Sox are the navy blue dot.

Over the past 12 seasons, teams that have hit more fly balls have just plain hit much better. An increase of two percentage points in fly ball rate is associated with a six-point increase in wRC+. Now, that’s not just due to fly ball rate. It’s also due to the fact that the smarter teams have caught on to the importance of elevating the ball and figured out how to find and develop players who can do so, and teams that are ahead in one area tend to be ahead in multiple areas. Still, I think the graph speaks for itself. I've written about how Romy Gonzalez has enough power to become a completely different player if he figures out how to lift the ball, and how Rob Refsnyder seemed to take that step last season.

In case you’re wondering, Roman Anthony's batted ball stats have followed a similar trajectory to Campbell's. In fact, when Jarrett Seidler broke down Baseball Prospectus's recent prospect rankings, he wrote, "Boston’s track record of swing speed and plane improvements is very real; Anthony himself is perhaps the biggest example of that in recent years." In his three years with the organization, Anthony's fly ball rate has gone from 20% to 24% to 31%, and his ISO has gone from .056 to .194 to .207. This is not an accident. Here’s how Red Sox hitting coordinator John Soteropulos described to Laurila what the team wanted Campbell to work on:

"His development program focused on two key objectives, improving ball flight and increasing bat speed. On the ball flight front, we identified specific bio-mechanical markers in his swing that needed refinement. The most significant factor affecting his bat path was the way his torso moved throughout the swing. Since the bat rotates around the spine, his excessive forward lean toward the pitcher created a steep bat path with low attack angles. We implemented a structured training program designed to address these inefficiencies, alongside other areas of focus.”

I have to tell you, coach-speak aside, this is exactly what I want to hear from the Red Sox right now. They’re embracing biomechanical analysis, which is the new frontier in player in development. They’re emphasizing bat speed. They’re not just telling players to elevate the ball; they’re helping them do so with instruction tailored to the way their body moves and they're finding success. Regardless of whether or not they turn into stars at the big-league level, Anthony and Campbell wings for the team’s scouting and drafting apparatus, but the biggest wins are on the player development side. They didn’t come to the team as top prospects; the team helped them become top prospects.

Interested in learning more about the Boston Red Sox's top prospects? Check out our comprehensive top prospects list that includes up-to-date stats, articles and videos about every prospect, scouting reports, and more!