LOS ANGELES — With left-hander Jordan Montgomery becoming the latest Diamondbacks starter to land on the injured list on Tuesday, the club is digging even deeper into its starting pitching depth.
This time, the next man up is 21-year-old Triple-A prospect Cristian Mena. Mena was recalled from Reno on Wednesday to make his big-league debut against the Los Angeles Dodgers. Mena will become the youngest starter to debut with the Diamondbacks since the late Tyler Skaggs on Aug. 22, 2012.
“He’s 21 years old, and he acts like he’s 30 years old,” manager Torey Lovullo said. “And that goes a long way with me when I’m gonna choose to put somebody in this environment, in this stadium.”
“He’s going to get into his rhythm and settle in and go out and execute a game plan.”
Mena is slated to face Shohei Ohtani as his first opposing hitter in the big leagues; not exactly a soft landing.
The Diamondbacks acquired Mena over the offseason in a one-for-one swap with the Chicago White Sox that sent outfielder Dominic Fletcher back to Chicago. In 82 2/3 innings at Triple-A Reno this year, Mena has a 4.90 ERA, 1.49 WHIP and 89 strikeouts compared to 38 walks.
While those numbers do not jump off the page, it is worth mentioning that the league average ERA in the Pacific Coast League this year is 5.44.
Ranked by MLB Pipeline as the Diamondbacks’ No. 11 prospect, Mena has a five-pitch mix that includes a four-seam fastball, curveball, slider, changeup and occasional sinker. At his best, he has shown flashes of dominance in the minors.
Mena’s Wipeout secondary pitches
If you love great breaking stuff, you’ll love Mena. This year in Triple-A, the young right-hander has thrown a curveball or slider almost half the time, and those pitches have whiff rates of 33.2 percent and 42.9 percent, respectively.
When opposing hitters do put them in play, they don’t typically do much. The PCL has hit just .173 with a .337 slugging percentage against Mena’s curveball this year. It has hit .160 with a .284 slugging percentage against his slider.
For reference, Brandon Pfaadt’s sweeper, which has proven to be an effective out-pitch in the majors, had a whiff rate of 37.9 percent during his time in Triple-A in 2022-23. Opposing batters hit .193 against it with a .372 slugging percentage. Mena’s breaking pitches could be similarly effective.
Against lefties, Mena nearly ditches the slider completely, relying heavily on his curveball and changeup. The changeup is hard, with an average velocity of 90.1 mph. It’s been effective this year, with a 28.7 percent whiff rate and an opponent average of .208 with a .302 slugging percentage.
Looking solely at the quality of Mena’s secondary pitches, it is not all that hard to envision a well-above-average big-league starter. But there is one thing that has held him back to date.
Fastball effectiveness
Mena’s fastball velocity is not alarmingly low, with a season average of 93.1 mph and good extension that ups his perceived velocity to 94.5 mph on average. But, for probably a variety of reasons, it has gotten crushed.
So far this year in Reno, opposing hitters have hit a torrid .482 with an .871 slugging percentage against Mena’s four-seamer. The expected stats come in a tad lower at .357 and .611, respectively, but those numbers are hardly comforting.
Mena’s fastball velocity appeared to tick up during spring training, but that increase has not carried over to the regular season.
“When the velocity ticks up, he’s even better, but that’s less of the concern,” farm director Shaun Larkin told PHNX Sports in our April prospect report. “It’s more of just, hey, let’s just get him in the zone more consistently, and utilizing what he does have, getting weak contact, getting ground balls, getting ahead and staying ahead, that type of stuff.”
It is worth noting that the high-elevation environments in the PCL do not just make balls fly farther. They also make pitches move less. Mena’s four-seamer figures to have more life at sea level than it has had in the minors this year. Whether that makes a significant difference remains to be seen.
Fastball command has also been an issue for Mena. He has thrown just 44.5 percent of his four-seamers in the strike zone this year, well below the big-league average of 55.8 percent. Among Diamondbacks pitchers who throw four-seamers at a clip of 10 percent or more, none have thrown a lower rate of them in the zone than Mena.
Inevitably, not throwing enough fastballs in the zone leads to walks, and that has been the case for Mena. His walk rate in Reno this year was 10.4 percent. That is far from alarming, but about two percentage points higher than the league average.
Mena has thrown 12 percent of his four-seamers this year in what Baseball Savant deems the “waste” zone. These are pitches that are just too far away from the zone to be competitive.
The fact that Mena has a clean, simple delivery inspires confidence that better command could come with time.
In the meantime, it seems possible that Mena will look to hide his four-seamer a bit in the majors and rely more on his secondary stuff. By all indications, his off-speed pitches could be good enough to make that a viable plan.
Top photo: Rob Schumacher/The Republic
