Diamondbacks 2023 Player Reviews: Ryne Nelson

The Diamondbacks' young starter had a rocky 2023 campaign.

This article is part of a series of player reviews for the 2023 Arizona Diamondbacks. It was a surprising and marvelous year for the team as they won 84 games to make the postseason. They advanced all the way to Game Five of the World Series before bowing out to the Texas Rangers. There are 54 players in all that had at least one at-bat or pitched at least one inning for the team this past season. They are being presented in reverse order of their aWAR (average WAR-Wins Above Replacement) produced, which is the average of Baseball Reference and Fangraphs WAR. These are their season stories.

Ryne Nelson's 2023 was shaky, despite some flashes of potential / Alex D'Agostino

The D-backs came into 2023 with some questions surrounding their starting rotation. Rookie starter Ryne Nelson--Arizona's second-round pick out of Oregon in 2019--won the fifth starting spot away from left-hander Tommy Henry and right-hander Drey Jameson.

But Nelson struggled through most of 2023. After an extremely brief stint in the majors in 2022, the young right-hander was poised to take on his first full season as a major league starting pitcher. His season began with a bang, as he allowed 22 earned runs in his first month, despite only pitching past five full innings twice. An ugly 6.39 April ERA and 1.52 WHIP was an ominous start to his first full season. 

May was a slight improvement, as Nelson marked his first scoreless outing since his second major league start back in 2022, but the right-hander's inconsistency continued to plague the D-backs. Although his monthly ERA hovered just above 4.00 through June, Nelson's performances were stressful at best.

Nelson flashed some potential mid-season, as he began to put out quality starts in late June, and even pitched into the seventh inning or later in back-to-back starts. He was, however, hit for seven runs over three innings in his subsequent start against the New York Mets.

Even so, while it looked like his Quality Starts were becoming more frequent, opponents were still hitting him at a .282 clip, and his strikeout numbers continued to decline, with a 17/8 K/BB in a July that saw him pitch three outings where he recorded just one strikeout.

The D-backs had little choice but to continue to give starts to Nelson throughout 2023, with left-hander Madison Bumgarner being designated for assignment in April and right-hander Zach Davies spending time on the Injured List. Shortly after calling up right-hander Slade Cecconi, Nelson was sent down to AAA on August 13th. The move came after Nelson pitched just six innings over two starts, allowing 12 earned runs and 15 hits. 

In Reno, Nelson looked solid, with a 3.74 ERA and 1.20 WHIP. However, he was called back up to the majors after less than a month and delivered a solid start, allowing just one run over 5 2/3 innings to help Arizona sweep the Chicago Cubs in the heat of a September playoff push.

Shortly after, Nelson was relegated to bullpen duties, pitching a scoreless inning in relief of the regular season finale against the Houston Astros. Nelson made the playoff roster as a reliever. In his first playoff action, the right-hander allowed three hits, while only recording one out in game two of the National League Wild Card in Milwaukee. He struggled again in his next playoff appearance, allowing four hits and three runs in just 2/3 innings against the Philadelphia Phillies in the second game of the National League Championship Series.

However, his final game of 2023 came in game four of the World Series. A bullpen game that went awry from the second inning, Nelson entered in the fourth inning and tossed 5 1/3 innings of one-run ball, recording six strikeouts and allowing just three hits. A lengthy bullpen outing that mirrored some of his best starts of the regular season. He finished his regular season with a 5.31 ERA and a 96/46 K/BB and a 6.0 K/9.

His playoff ERA of 5.68 came from a small sample size, skewed by one exceptionally poor outing, but opponents hit .357 against the young right-hander throughout the postseason. 

According to Baseball Savant, Nelson's pitching run value was -23 in 2023, and he ranked near or below the bottom 10 percent in whiff percentage, strikeout percentage exit velocity and chase rate. Opponents hit Nelson hard, and they rarely missed. Despite all his issues, he still accounted for a positive 0.37 aWAR, and showed flashes of ability to produce Quality Starts. 

2024 Status and Outlook

2023 was not Ryne Nelson's year, but it's too early in the young right-hander's career to disregard potential for improvement. However, with the notable rise of rookie right-hander Brandon Pfaadt, the likely return of young left-hander Tommy Henry, and the signing of veteran left-hander Eduardo Rodriguez, it's hard to envision a situation--barring injury--where Nelson is able to win a spot in the rotation. Nelson will likely see most of his action coming out of the bullpen in the future, and could potentially spend some time down in AAA, depending on the status of right-handers Bryce Jarvis and Slade Cecconi.