After the departure of Corbin Burnes, who follows Merrill Kelly?
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There’s no denying that the loss of Corbin Burnes for a year or more was a devastating body-blow to the D-backs. The team expanded payroll to its largest ever level to make room for the signing of Burnes, but between him and Jordan Montgomery, the team is paying $54.2 million to pitchers who won’t take the mound again this year, due to Tommy John surgery [and that number could go up, depending on what happens with Justin Martinez’s second opinion]. After a wobbly first couple of outings, Corbin had been the ace we wanted, with a 1.84 ERA over his final eight outings, with six quality starts. But the rotation now has to re-organize.
Merrill Kelly now becomes the de facto #1, with an ERA (3.18) and FIP (3.23) which are clearly the best of Arizona’s starting pitchers this year. But who do you feel is the D-backs #2 starter this year? It’s a significant question, especially if the team were to make the post-season, because they’re likely to start as often as Kelly. The numbers for all four of the team’s other starters have been… mixed, shall we say. None of them have an ERA+ higher than ninety, indicating they have all been clearly below league average thus far in 2025. But you can also find some reason for optimism with all four. So let’s take a look at each candidate and then you can pick who you consider the team’s #2 starting pitcher.
Zac Gallen – 4-8, 5.15 ERA, 4.90 FIP. I would say that peak Gallen is potentially the best pitcher in the bunch, and in his walk year, there should be every motivation for Zac to want to perform well. However, this doesn’t seem to have worked out as expected to date. In particular, he has walked an NL leading 36 batters so far. Just eleven more, and Gallen will have matched his total for the entirety of the 2023 season, when he made 34 starts and threw 210 innings. The strikeouts are also below one per inning for the first time in Zac’s career. He’ll need to do better than that going forward.
Ryne Nelson – 2-2, 4.60 ERA, 3.68 FIP. Nelson has been jerked between the bullpen and the rotation, and has yet to make more than two consecutive starts. However, he should now have a chance to establish himself long-term as a starter. Despite the rule uncertainty, he has done credibly well, and his 0.5 bWAR is the best of this quartet. He will need to lengthen out, not having reached even 85 pitches this year. In his four starts, he has only once got an out past the end of the fifth. But Ryne has been good at keeping the ball in the park, allowing only four home-runs over his 45 total innings of work.
Brandon Pfaadt – 8-4, 5.50 ERA, 5.13 FIP. The youngest candidate, Pfaadt might have the most potential upside, He was a consensus Top 100 prospect before 2023, and Jack was not alone in tipping him for a breakout campaign this season. But as in 2024, the problem has been in converting that potential to consistent results. This year, he hasn’t been missing many bats – the infamous start against LA without a swinging strike stands out – and he has been vulnerable to the long-ball, allowing fourteen in 70.1 innings. His K-rate of seven per nine IP is consequently well below what you’d expect from any pitcher.
Eduardo Rodriguez – 2-3, 6.27 ERA, 4.28 FIP. The man with most experience and, given the length and cost of his contract, arguably the one whose performance is most important to the team going forward. There is a large gap between his ERA and FIP: of the 117 pitchers with 50+ IP, only four have a bigger difference. Meeting the FIP going forward would go a long way to help, and Rodriguez has been a lot better since coming off the IL. Small sample size (two starts), but 3.18 ERA – the FIP of 4.23 is almost unchanged. A particular improvement, he has walked just one of 46 batters faced post-IL.
So, who have you got?
Feel free to provide an explanation for your choice in the comments. The results will follow over the weekend.