Diamondbacks 2024 Player Projections: Kyle Nelson

Nelson's ERA and FIP don't change an extreme amount. A 4.07 ERA isn't the worst number, but still sits well above his career best 2.19. He's projected to continue to strike out batters at a solid rate, but less frequently than in 2023, and his walk rate is expected to return closer to the mean, nearly doubling his 2023 rate to sit just behind of his 2022 percentage. 

He's expected to give up fewer home runs, and our playing time projections have him taking a reduced role, but still working a decent number of innings at 41.0 His aWAR signify him being of some value, but not quite living up to the potential he's shown in the past.

Why Nelson might outperform this projection

Nelson's numbers are very intriguing. In a year where he pitched to an overall much worse eye test and ERA than 2022, some of his underlying numbers were extremely good. Although allowing an average of two more runs than 2022, he increased his strikeout rate by nearly 10%, and almost halved his walk rate, despite having some issues with control and walks in 2023.

Where Nelson has been developing, despite a down year, has been in the swing-and-miss department. Nelson sported a top 20% whiff rate and strikeout rate, and ranked in MLB's 95th percentile in getting batters to chase outside the zone. 

His xERA and xBA were both well above average, backing up that his numbers might have been somewhat inflated by the "unluckiness" inherent in a .331 BABIP for 2023.

His arsenal consists of a solid slider that tends to trail well outside the zone as his primary pitch, as well as a low-90s fastball and erratic, seldom-used cutter. By all accounts Nelson is a swing-and-miss, deception pitcher, who relies on chases.

His xERA and xBA were both well above average, backing up that his numbers might have been somewhat inflated by the "unluckiness" inherent in a .331 BABIP for 2023.

Curiously, Nelson had a 2.86 ERA in road games, whereas he had a 5.53 at Chase Field in a nearly identical number of innings. Nelson strung together a month's worth of 3.48 or better ERA three times in 2023, with his inflated numbers generally coming from a couple of rougher months. 

He allowed high averages across the board in high leverage innings. Now that he likely won't have to take on a critical role with the back end of the bullpen solidified, he can excel at middle innings in lower-pressure situations.

Nelson, as a younger arm without a great deal of experience, has shown his prowess to be a very solid left-handed arm. He's able to string together good stretches, and has been a strength of this bullpen. Although having a somewhat down year, Nelson could easily surpass his projections, since his tools allow him to be a good spot reliever in a more defined role. Especially considering he suffered a tough stretch of batted ball luck, and was put into a few clean-up positions that inflated his numbers, he, by all accounts, can be a much better arm than his 2023 numbers showed.

Why Nelson might underperform this projection

Nelson has struggled with walks in his career, and tends to get hit very hard. His control can be an issue, leaving low-velocity pitches hanging over the plate or sending them so far outside the zone one can only pray for a chase. 

Although striking out batters and making them chase wasn't an issue for Nelson, he still sported negative run values on both his fastball and breaking balls. His barrel rate and hard-hit rate ranked in the bottom half of MLB, and he failed to produce ground balls and soft contact. 

With a limited arsenal, and one main trick, Nelson could struggle to pitch well again in 2024. If his control isn't there, we could easily see his walks spike again, and the more pitches he misses, the more opportunity will be for him to allow a skyrocketing slug percentage.

Nelson will likely have a decreased role with the club in 2024. Although he won't find difficulty making the team, his numbers could suffer more from a couple of rough outings, and with the potential for young left-hander Andrew Saalfrank to break out, Nelson will have to work on his control and consistency to avoid being stuck in a mop-up role, banished to middle innings or blowouts.

It's possible that Nelson's discouraging ability to get hit very hard, along with his nearly 2.0 home runs per nine from 2023 continues, and his numbers could look worse than they did last season.

Summary

Nelson has been a solid arm for the D-backs. His projections show slight improvement to a decent to average season in 2024. While he's been excellent at getting opponents to chase and strike out, he also has a tendency to sail pitches far outside the zone, or leave them hanging over the plate. He could easily return to his 2022 form, or continue a downward trajectory.