Today’s Comps for Tomorrow’s Aces: Part 2

For many of us, our fantasy baseball seasons are effectively over. It wasn’t our year. But instead of sulking, something many of us do so well is to immediately turn to draft prep and the next season. 

In doing that, part of the process is looking back at the season to see some of the emerging young players and ascertain whether or not their emergence was real and repeatable. One of the classic ways to do this is by looking for comparisons of these young players to established major leaguers to serve as proof of concepts. 

Scouts have done this forever and it has worked in the recent past. Hunter Brown’s association to Justin Verlander foreshadowed the former’s rise to ace status. Many in the industry connected Parker Messick’s arsenal and style of pitching with Hyun-Jin Ryu, and Messick has had similar results so far. Chase Burns’ reliance on the fastball and slider was compared to a young Spencer Strider’s prior to the former’s debut, and Burns has been just as good as the vintage version of Strider. 

Over the course of the next few months, I’ll provide a handful of potentially instructive comps we can make to help illuminate this growing crop of young starting pitchers.

For Part 1 of this series, where I find comps for today’s young emerging aces, I took a look at the Mariners’ Kade Anderson, comparing his arsenal, arm slot, and potential prospect arc to that of perennial All Star, Max Fried. 

Today, I’ll compare two Dominican flamethrowers in Angels’ rookie Walbert Ureña and Marlins’ veteran Sandy Alcantara.

Walbert Ureña & Sandy Alcantara

Sugar Ray’s Mark McGrath made a habit of singing that “every mornin’ there’s a halo hanging from the corner” throughout the early 2000’s. He may have been having visions of Walbert Ureña’s changeup. That’s how I felt Saturday afternoon anyway, watching the rookie hurl changeups past James Wood and the Nationals’ lineup, one of baseball’s best in 2026, with regularity. 

Ureña, in his first campaign in the majors at 22 years old, has shown elite command of his changeup. The right-hander has earned a 109 Location+ on the pitch, his primary offering to left-handed batters, as he’s kept it in the shadow of the zone 42.6% of the time. 

Thanks to stellar locati0n and a 7 mph gap between his hard sinker and changeup, Ureña has a .177 batting average against his changeup this season, earning him a pitch value of over 15 with the pitch. He is in the 100th percentile among qualifiers this season for run value on his offspeed offering. 

Back in 2021, another hard-throwing sinkerballer was dominating with a changeup. Sandy Alcantara was in the 92nd percentile for offspeed run value that season. Alcantara had nearly a 6 mph gap between his sinker and changeup and a 101 Location+. He kept the pitch in the shadow of the zone 45.7% of the time. Alcantara allowed a .228 AVG against his changeup in his first full season in the majors.

In 2022, Alcantara had his best season with the changeup, allowing a .145 AVG against and finishing with an 18.4% SwStr% and 24.5 pitch value. Watch him carve up Bryce Harper with the pitch a few times, during both of their respective peaks.

In 2022, Alcantara combined dominance and pinpoint command on his way to winning the NL Cy Young. With all four of his primary pitches, each thrown at least 20% of the time, he had a Stuff+ of over 100 and Pitching+ over 105. He allowed the lowest Pull Air% against of his career, down at 12.3%, and his best Barrel% at 5.3%. He had a career-high 53.4% groundball rate, a sub-2 BB/9, and finished with 228.2 innings and a 2.28 ERA. 

I think Ureña has a similar ceiling. It may just take one or two steps forward to get there. 

So far, I’ve focused on the changeups for each of these pitchers. But really, it’s the full arsenals for both that are remarkably similar. 

At the trade deadline, Michael Baumann covered Ureña for Fangraphs, comparing him to the recently-dealt José Soriano as the heir apparent rotation topper for the Halos and to, well, Chris Devenski. He bemoaned Ureña’s lack of swing-and-miss stuff. The scouting reports backed this up, showing how Ureña’s fastball and cutter got absolutely smacked around in the minors. He threw either the fastball or cutter more than 75% of the time in the minors. 

As Baumann noted at the time, Ureña has had a much deeper arsenal at the major league level, primarily due to his aforementioned changeup, and also because he ditched the cutter for a sweeper, adding another lower velocity pitch to his mix. 

This shift brought him much more in line with Alcantara’s Cy Young arsenal. 

See how Alcantara’s movement profile (on the left) lines up with Ureña’s (on the right)? 

Both pitchers used these mixes in similar ways. Both relied on their changeups and four-seamers against left-handed hitters and used their sinkers and glove side breaking pitches against right-handed hitters. For Alcantara, he used a cutter, while Ureña uses a sweeper. 

For the most part, they had similar results. High groundball rates, both well above 50% and at least in the 90th percentile in the majors, helped keep their ERAs low, with Ureña sitting at a 2.88 ERA, impressive for any pitcher, let alone a rookie. Neither was particularly adept at strike outs, despite their elite fastball and sinker velocities, both sitting around an 8 K/9. 

They also both have easy velocity, rarely reaching back for their maximum velocities (around 10% of the time for both), which may help limit injuries. 

In Alcantara’s case, he missed 2024 with an elbow injury, but exceeded 174 innings every other year from 2019 through 2026 (excluding 2020).  

Now, before any of you comment about the five inches in height that separate the 6’5 Alcantara and 6’0 Ureña, I do want to acknowledge that it is a big difference. But it isn’t going to change. 

The three biggest differences between the two, and thus the three biggest growth opportunities for Ureña, are things he can change: strike throwing, success with fastballs, and generating chase. 

Let’s start with throwing strikes, because history would tell us this is something that can be taught. Not to everyone, but it can be taught. 

Alcantara reached 228.2 innings in 2022, in large part, because of a teeny tiny 5.6% walk rate. He was 26 years old when he reached this pinnacle. He’d already had a strong 2021, with a 6% walk rate and more than 200 innings. 

But in 2019, his first full season in the bigs, he had a 9.7% walk rate. From 2021 through 2026, Alcantara has maintained a 6.4% walk rate. But in his age 21-24 seasons, from 2017 to 2020, Alcantara looked a lot more like Ureña has so far, with a 10.5% walk rate over those 281.2 innings. 

Alcantara learned to rein in his wicked movement and throw strikes. He brought his Zone% up from 47.9% across his age 21-24 seasons to 51.8% in the years since. Ureña has a 45.8% Zone% as a 22-year-old this season. And the good news is, Ureña seemed to improve in this regard as the season progressed. 

Being in the zone more often, theoretically, should help him find more success with fastballs and generate more chase. 

When Ureña has been ahead in the count this season, all of his pitches have earned a positive run value. When he has been behind in the count, every pitch but his changeup has had a negative run value. When he is behind in the count, his xFIP shoots up to 6.86. 

The clearest illustration of this is the difference between Ureña’s outcomes on 1-0 and 0-1 counts this season. Ureña has a 28.5% K-BB% and 2.31 xFIP when gets ahead 0-1 to start a hitter off. He threw a first pitch strike 55.9% of the time this season. 

But in the 44% of plate appearances where he didn’t, falling behind 1-0, he had a 19.8% walk rate, a negative K-BB%, and a 6.10 xFIP. If he can increase his first pitch strike rate, it would follow that he can have better results. Specifically, he should walk less hitters if he gets to 0-1 more often.

Alcantara had a first pitch strike rate of 60% or higher every season after his initial cup of coffee as a 21-year-old with the Cardinals in 2017, so there is hope for Ureña.

The dramatic shift in results for Ureña is likely due to the change in his pitch mix when he falls behind. 

He tries to use his changeup as a bailout pitch when behind, but really, he has to throw his fastballs more, at the expense of his sweeper. While overall, Ureña’s sinker has a 2.8 pitch value this season, it fares much worse when thrown from behind in the count. 

When behind in the count, Ureña allows a .440 xWOBA against his sinker. Essentially, falling behind in the count makes him use one of his nastiest, most successful pitches to be something hitters expect to see, and a pitch they take advantage of. When he’s ahead, and can use the pitch as a weak contact generator or swing and miss offering with his changeup, he allows a meager .175 xwOBA against his sinker. The same story is repeated across his arsenal. 

Ureña has impressive O-Swing% numbers on all four of his pitches overall, with the changeup being the only pitch over 30% at a stellar 37.7%. Chasing the changeup generates whiffs and weak contact, which was Alcantara’s calling card at his peak. He can also use his sweeper, with its 13% swinging strike rate, more often if he gets ahead more often, since it is essentially not usable in hitter’s counts. 

With his high groundball rate and nasty stuff, Ureña can make the ace turn if he follows in Alcantara’s footsteps by throwing more strikes to get ahead in the count more often. Even this season, limiting walks let him go deeper into starts.

Ureña had 13 starts of six or more innings this season. In all 13, he walked three batters or less. In 2022, Alcantara walked more than three batters in just two of his 32 starts. This helped Alcantara be an especially dominant fantasy asset in points leagues and in head-to-head categories leagues with quality starts. In Ureña’s 13 starts six-plus inning starts, he earned 12 quality starts.

Watch Ureña in Spring Training. For Alcantara, his Spring walk rates actually did foreshadow his regular season walk rates. He didn’t have any walks in his 2022 Spring Training, albeit in 7 innings. 

But really, just watch Ureña in the early part of next season. If he can rattle off a few early starts with less walks than his projected 10% rate, he could really see improved results in a hurry.