The Arizona Diamondbacks starting rotation is set. After a mixed 2024 campaign which was ravaged by injuries and damaged by inconsistency, 2025 is shaping up to be more promising. With a mix of veteran talent and a young up-and-coming arm, the D-backs could potentially have one of the best starting rotations in all of Major League Baseball if things pan out the way they should.

The Starting five

Zac Gallen

On Thursday, manager Torey Lovullo revealed Gallen would be getting the Opening Day start for the Arizona Diamondbacks. This marks Gallen’s third Opening Day start, making him the sixth D-backs pitcher to make at least three of these starts, the others being Madison Bumgarner (3), Zack Greinke (3), Ian Kennedy (3), Brandon Webb (4) and Randy Johnson (6). The Milkman is coming off a down season by his standards with an ERA+ of 115 (100 is league average) in 28 starts across just 148 innings pitched. Still, Gallen is one of the faces of the franchise and a down year by his standards is often a career-year for other pitchers.

Gallen has been a mainstay of the D-backs since he arrived via trade from Miami in 2019 and has led the team through a 110-loss season in 2021 to some of its greatest heights such as the 2023 World Series appearance. With that being said, Lovullo felt Gallen deserved yet another spot atop the team’s rotation.

“I’m super appreciative that (Lovullo) was able to give me that honor,” Gallen said. “We have a bunch of guys in here deserving of that honor so it’s something I’m proud of.”

Corbin Burnes

Burnes was the big-name acquisition this offseason for the D-backs, signing for six years and $210 million. While it would be expected he would get the Opening Day start, Gallen’s seniority within the organization would push Burnes to the second start of the season. Because of some scheduling errors where he was expecting to start Opening Day and now won’t, Burnes will make his debut against the Yankees on April 1.

“While I was taking my time, which I thought was being the most responsible thing, I was, throwing the rhythm off as to the time that we had on the backside of it,” Lovullo said. “So that’s where I blame myself.”

But most teams would kill to have a one-two combination of Gallen and Burnes atop their rotation. Not sending out Burnes first is a luxury that the D-backs can afford. Burnes is coming off a year with the Baltimore Orioles which saw him remain effective even with declining strikeout numbers. Still, his 8.4 K/9 rate from last year is around the league average. The 2021 NL Cy Young Award winner projects to put up a 3.33 ERA and 3.39 FIP across 188 innings, according to FanGraphs. Now making his offseason home his full-time home, Burnes could be in for another elite year for the D-backs.

Merrill Kelly

Generally unheralded outside of D-backs fans throughout his time in the majors, Kelly has been a stalwart of Arizona’s rotation Since coming back stateside after four years pitching in Korea. While it was a down year for him last season, it was in part because Kelly missed much of the year with injury.

In April, he was placed on the injured list with a teres major strain in his right shoulder and was only able to pitch 73.2 innings last year. Utilizing a cutter/changeup combo, Kelly has been a reliable source of outs for the D-backs and that isn’t expected to change in 2025. Baseball Savant rates his off-speed pitch run value in the 97th percentile while his walk rate is in the 77th and chase rate in the 70th percentile.

Eduardo Rodriguez

The first lefty up in the rotation, E-Rod is looking to rebound after the worst season of his career, one in which he made just 10 starts because of injuries and the only time his ERA has ever ballooned above 5.00. Rodriguez seemed to get things together at the end of last season though, pitching to a 3.92 ERA in his final four starts along with 29 strikeouts in 20 innings pitched.

Similar to Kelly, Rodriguez mostly utilizes a fastball/changeup mix while also incorporating a slider every now and again. People across the league know Rodriguez is worth his contract he signed with the D-backs during the 2023-24 offseason where he was coming off a year in which he had an ERA of 3.30 and was highly coveted by the NL West-winning Dodgers before he exercised his no-trade clause to decline a trade there from Detroit. With his family now living in the Phoenix area and a fully healthy offseason, expect Rodriguez to fully settle in and be prepared for productive first full season with the D-backs.

Brandon Pfaadt

Coming off an excellent 2023 postseason where he had a 3.27 ERA, including a nine strikeout performance against the Phillies who boasted one of the best offenses in baseball, big things were expected of Brandon Pfaadt entering 2024. Things didn’t quite go according to plan, with him tiring out in the second half and unfortunately ending the year with a 4.71 ERA after a strong start through August. On the bright side, he was one of the only pitchers who managed to stay healthy for the D-backs, making 32 starts in the year and leading the club in innings pitched.

It was widely expected that Pfaadt would be battling it out with Jordan Montgomery and Ryne Nelson for the fifth and final rotation spot. A combination of a strong spring training, the news that Jordan Montgomery will need to undergo Tommy John surgery and miss the entire season and a poorer spring by Nelson ensured Pfaadt received a spot in the starting rotation. Now that he’s had a full season under his belt, perhaps we can expect Pfaadt to have a 2025 more similar to his first half of 2024 than his second half.