Projected Diamondbacks rotation after signing Jordan Montgomery

On Tuesday night, the Arizona Diamondbacks reached an agreement on a deal to bring southpaw Jordan Montgomery to the desert. This finally brings an end to his long offseason and also means that Scott Boras officially got his big four guys signed.

Ken Rosenthal of The Athletic reported that Montgomery's deal will pay him $25 million this season with a vesting option for a second year. Jon Heyman of the New York Post reports that the option is based on how many starts Montgomery makes in 2024. If he makes ten starts, he can opt out of the deal, or his salary would be $20 million in 2025. It boosts to $22.5 million if he makes 18 starts and to $25 million if he makes 23 starts.

An interesting deal, and yet another short-term contract for a Scott Boras client. With Montgomery landing in Arizona, it adds yet another big name that is headed to the NL West, and boosts an already strong Diamondbacks rotation coming off of a World Series appearance.

Diamondbacks rotation with Jordan Montgomery

Montgomery probably won't be ready for a while, likely closer to May than not. And, as of now, their other free agency acquisition, Eduardo Rodriguez, is on the injured list. Rodriguez was diagnosed with a lat strain, but how much time he will miss is still up in the air. With both pitchers slated to miss some time, the Diamondbacks rotation won't be at full strength for a while, but it is projected to be very strong when it is.

1. Zac Gallen

Everyone knows about Zac Gallen, Arizona's ace. Since Arizona swapped Jazz Chisholm to get him, he has been Arizona's most reliable pitchers and has proven himself to be one of the best in the game. In 2023, he threw 210 innings to the tune of a 3.47 ERA and struck out 9.4 batters per nine, earning him his first All-Star nod and a third-place finish in the Cy Young.

With Gallen's breakout last year, he is a pitcher that can be slotted into the No. 1 spot in the rotation and be left there. He will look to repeat his 2023 campaign and even improve on it in 2024 and will once again be the ace of the rotation.

2. Merrill Kelly

Kelly is coming off the best season of his career since coming back from Korea, throwing 177.2 innings with a 3.29 ERA and 9.5 K/9. Not only that, but he was dominant during the World Series run, including a seven-inning, one-run performance in his one game against the Texas Rangers. He will look to continue that performance heading into 2024.

A steady arm, Kelly will provide innings that will be much-needed at the beginning of the season. He's not an ace at the level of Gallen, but he proved in the postseason that he has the capability to break out to another level. At the very least, the floor is someone who will pitch 30 games and throw 175+ innings.

3. Eduardo Rodriguez

As previously mentioned, Rodriguez is going to begin the season on the injured list. When he gets back, though, he will immediately slot into the rotation as one of their top arms.

Coming off his best season, the 30-year-old received a four-year, $80 million deal with Arizona this winter. In 26 games in 2023, he threw 152.2 innings with a 3.30 ERA. With an 8.4 K/9 last year, he was down from his career average of 9.1, but he can still miss some bats. Like Kelly, his numbers may not wow you, but he will provide good innings on a consistent basis upon his return.

While it's not known when he will be back from the injury just yet, when you look at his career numbers, you pretty much know what to expect from him.

4. Jordan Montgomery

The new addition, Montgomery will also miss time, though not due to injury, just due to signing late and needing to ramp up to game-ready. If there's one thing Montgomery will do, it's post innings year in and year out. If I said "reliable" or "steady," the theme becomes abundantly clear as to what Arizona is building with their rotation.

Another guy coming off of a career year, Montgomery threw 188.2 innings with both the St. Louis Cardinals and Texas Rangers. He posted a 3.20 ERA, but in 11 regular season starts with Texas, he had a 2.79 ERA. Then, when he got to the playoffs, he allowed just 10 earned runs in 30.3 innings, including 6.1 shutout against the Houston Astros in the ALCS.

With the signing being so fresh, the timetable for his return is not yet known. When he gets back, he will add yet another innings eater to this rotation.

5. Brandon Pfaadt

Pfaadt is a pitcher to keep an eye on this year in terms of breakout potential. While he struggled in the regular season, with a 5.72 ERA in 96 innings, he really began to show his upside in the playoffs.

He pitched in five games, throwing 22 innings with 26 strikeouts. He began to catch the eyes of more people during the NLCS when he threw 5.2 innings and strikeout nine while only allowing two hits against the Philadelphia Phillies.

He's someone to get excited about moving forward, especially when you look a little deeper. In 2022, Pfaadt threw 61.2 innings and struck out 74 with a 2.63 ERA in Triple-A Reno and the PCL is a notorious hitters league. Be on the lookout for Pfaadt in 2024.

In the absence of Montgomery and Rodriguez, the Diamondbacks have a couple of guys who can cover those starts. Namely, Ryne Nelson, who was a candidate to make the rotation before the signing. Nelson threw 144 big league innings last season, so he will be a favorite to fill that role. Other names include Tommy Henry, Blake Walston, Corbin Martinand Slade Cecconi.

With the signing of Montgomery, the Diamondbacks rotation becomes one of the best in all of baseball. While it may not be flashy, it's definitely old reliable, with a current star and a guy who can make the leap to be a star. The rotation allows them to stay a team that can make a playoff push.