Diamondbacks 2024 Camp Battles: Final Reliever

Making the case for and against three relievers in a competition for what could be the final Opening Day roster spot

The sixth and final camp battle we're highlighting at Inside the Diamondbacks will be the final spot in the bullpen. This is based off the assumption the team will likely carry two left-handers to start the season. 

The D-backs already will have Paul Sewald, Kevin Ginkel, Miguel Castro, Joe Mantiply, Scott McGough, and Ryan Thompson as locks, leaving just two spots up for grabs. One will go to a second lefty and the other could be determined if they want to carry a long reliever. 

These three pitchers have the best chance of making the roster. 

Ryne Nelson

At the start of the season, it makes more sense to convert Nelson to a reliever. They can keep him stretched out as a long reliever, considering the final two rotation spots are held by pitchers with fewer career starts. By moving him to the bullpen, that gives the D-backs the most flexibility in how manager Torey Lovullo can maneuver his bullpen early in the season. If Nelson shows the ability to get major league hitters out in this role, they can look at exploring a move to either the rotation or the back end of the bullpen.

Nelson projects as an innings-eater that can bridge the gap between the rotation and the back end of the bullpen in the event of a short start. His fastball and slider both ranked above 100 in Stuff+, and as a reliever he could focus on those two pitches for the time being. There is the makings for a usable changeup in his repertoire, in case he sees a lineup multiple times through. 

Corbin Martin

Martin was possibly on track to possibly make the D-backs Opening Day roster last year, but suffered a torn lat tendon throwing a pitch in a spring game. With the season likely lost, he elected to undergo surgery in the hopes that he would be 100% healthy at the start of camp in 2024.

Once a former top pitching prospect that was the centerpiece in the 2019 deadline deal for Zack Greinke, injuries have derailed Martin's career. At his best, he has a 96-97 MPH fastball with good carry and two quality breaking balls. For health reasons, he's likely more suited for shortened outings. The most important thing to see is if the quality of his pitches were the same as a year ago. If that is the case, then he could easily filter into the back of the D-backs bullpen as he grows more confident with each outing.

Martin's option situation is a bit unclear, as it's unknown if he still qualifies for a fourth option year. If not, then Arizona cannot stash him in the minors without exposing him to outright waivers and it's unlikely he would go unclaimed. 

Luis Frías

Frías is an out of options right-hander that flashes impressive stuff at times, but lacks the command and consistency to harness it. Beyond a fastball that averages 96 MPH, he has a low-90s cutter that can be a real tough pitch for hitters and a gyro slider in the mid 80s. He had a very good feel for the fastball and the cutter for much of the second half, but was inconsistent at landing the slider. That will need to improve in order to become a capable reliever.

Frías qualifies for the fourth option year, so the D-backs can call him up and send him down for one more season. With the raw stuff he possesses plus the progress he made in 2023, one more year could be critical It's possible that the team could carry him instead of a long man, with all of their starting pitching depth capable of being optioned to the minors. However that would create a logjam with the Reno rotation.

Verdict

Despite it being a battle of two unknowns, it makes the most sense to carry Nelson over both Martin and Frías. Since he is out of options, that would expose Frías to waivers but given his raw stuff could have some potential suitors looking to buy-low on a high octane bullpen arm. That may be the same reason that the D-backs hold onto Frías to start the season as well, although his track record has been poor throughout his brief MLB career.