White Sox Deep Dive: Rookie League Left-Handed Starters
Tommy Sommer and Ronaldo Guzman headline this group of southpaws.
“Deep Dive” focuses on the depth of each position in the Chicago White Sox organization. Each position is broken into a five-part series:
- Depth in the rookie levels (Dominican and Arizona)
- Depth in A-ball (Kannapolis and Winston-Salem)
- Depth in the higher levels (Birmingham and Charlotte)
- Under the Radar-type detail on a White Sox player
- Free agent options
White the White Sox system has several good southpaw relievers, its cupboard is considered relatively bare for the like-throwing starters. However, that doesn’t mean there isn’t talent in the pipeline. Below are the left-handed starters who finished the 2021 season in the rookie leagues.
Ages below are as of April 1, 2022
ACL White Sox
Tommy Sommer
6´4´´
220 pounds
Age: 23
Athletic ability doesn’t often fall too far from the tree. In Sommer’s case, his father Juergen was a goalkeeper for the Indiana University and part of their 1988 national championship team; he played for more than a decade in the professional ranks, ultimately concluding his career in 2004 with the New England Revolution. His mother was no slouch athletically, either, as she was a star high school softball player.
Sommer, a native of Carmel, Ind., pitched all four years for his father’s alma mater. Primarily a starter in his first two years, he started four games and did quite well with a 2.61 ERA and 1.07 WHIP until the pandemic concluded the 2020 season prematurely.
He picked a bad time to have his worst season, but Sommer did just that in 2021. In 12 starts for the Hoosiers totaling 62 2⁄3 innings, he posted a 4.60 ERA and 1.48 WHIP by relinquishing 55 hits (.237 OBA) and 38 walks while fanning 69. His 5.5 BB/9 was more than two walks per game worse than his previous high of 3.4 set in his junior year, but he also reached his career high in K/9 at 9.9.
As a four-year senior who lacked leverage, the White Sox drafted Sommer in the 10th round and signed him to a $20,000 bonus — $123,600 under slot value. Because he had already pitched the most innings of his career while with Indiana, Sommer was kept to a tight pitch count while with the ACL Sox. Against competition about a year younger than he, Sommer performed exceptionally well by producing a 2.16 ERA and 0.80 WHIP in his eight outings (six) starts. In 25 innings, Sommer surrendered a measly 13 hits (.149 OBA) and seven walks (2.5 BB/9) while striking out 33 (11.9 K/9). Review of these results, however, suggest some future regression, as Sommer’s FIP was 4.23 and his ground ball rate was just 30.2%.
Most importantly for Sommer, though, is that he stayed healthy last year while finishing the year with good control. Command will be key for him going forward, as his four-seamer typically runs 88-92 mph. As is necessary for someone with a heater that isn’t quite so hot, Sommer also features a complement of secondary offerings to keep hitters off-balance. His cutter cuts away from lefties but moves in on righties, which limits the quality of contact. His best offering is his changeup, which is often used as a put-away pitch. Finally, his fourth offering is a rudimentary curveball that is simply a show-me offering at this point.
With his size, control, senior-year struggles, velocity and repertoire, Sommer’s profile is similar to that of former Sox farmhand Konnor Pilkington. Expect Sommer to begin the season with Kannapolis, but there’s a chance he could begin the 2022 season in what looks to be a loaded Winston-Salem rotation.
Ronaldo Guzman
6´0´´
150 pounds
Age: 19
2020 SSS Top Prospect Ranking: 46
2021 SSS Top Prospect Ranking: 55
Guzman, a native of the Dominican Republic, received a $75,000 signing bonus on Oct. 29, 2018, which may turn out to be the best under-the-radar signing of an international pitcher ever for the White Sox. In his first taste of professional ball in 2019, he posted a 4.53 ERA and 1.39 WHIP in 14 outings (12 starts) spanning 51 2⁄3 innings. In those innings, he relinquished 43 hits (.221 OBA) and 29 walks (5.1 BB/9) while striking out a whopping 76 (13.2 K/9). While those numbers are outstanding for someone who didn’t turn 17 until late August, Guzman’s numbers would’ve been even better if not for one bad relief outing; you throw that bad boy away and you get an 3.53 ERA and 1.29 WHIP. Keep in mind, also, that Guzman was approximately 2.3 years younger than the DSL average. Certainly his walks were an issue, in addition to a low ground ball rate (37.9%).
Guzman, while striking out his fair share of hitters, struggled badly with his control during his first year Stateside, in 2021 after the 2020 season was lost to pandemic. In 14 games (eight starts) totaling 39 innings this year, Guzman posted an ugly 7.62 ERA and 2.21 WHIP by surrendering 38 hits (.250 OBA) and walking 48 (11.1 BB/9) while fanning 46 (10.6 K/9). Surprisingly, righties hit him less effectively (.228) than lefties (.294). While Guzman did relieve in six games, he fared much better as a starter (6.58 ERA, .245 OBA) WHIP) as opposed to relieving (9.69 ERA, .259 OBA). With any pitcher, it’s vital to get ahead in the count. Guzman, however, took that to an all other level with the ACL Sox:
Ahead in the count, hitters hit just .021 giving him a WHIP of 0.07
Behind in the count, hitters hit .429 off him with a 38.25 WHIP.
Ben Badler of Baseball America said this of Guzman prior to the 2019 season: “fastball that gets up to 89 mph with easy arm action and an athletic delivery that repeats well to throw strikes with an advanced changeup for his age.” FanGraphs said this of him after he participated in the 2020 fall instructional league: “he struck out a lot of DSL hitters in 2019 even though he only threw in the mid-80s because his fastball has big carry. He’s now into the upper-80s and will have an impact fastball if he can keep throwing harder.” Also, because righties hit him less than lefties, it’s safe to assume that he’s got an above-average changeup as well. It’d behoove him to focus on keeping the ball down, as a 29.8% ground ball rate this year was far worse than average.
All is not doom and gloom for Guzman. He still struck out an impressive amount of hitters, and if he can bulk up a bit, his fastball could be expected to gain a few ticks. Also, he was pitching against competition nearly three years older. Before working on forcing hitters to hit more worm-burners, he really needs to focus on improving that control. He has arguably highest ceiling among all the system’s southpaw starters, but he also has one of the lowest floors due to his lack of control and command. Based on his results this year, expect Guzman to return to the ACL Sox for the 2022 season.
DSL White Sox
Guillermo Cuevas
6´0´´
180 pounds
Age: 22
The 22-year-old Dominican native signed with the White Sox on July 16 and was immediately inserted into the DSL starting rotation. Not much was known about Cuevas, but 22 is definitely an advanced age for someone making his DSL debut. In eight appearances (seven starts), he compiled a respectable 4.64 ERA and 1.27 WHIP. In his 33 innings, Cuevas ceded 28 hits (.228 OBA) and 14 walks (3.8 BB/9) while striking out an impressive 47 (12.8 K/9). Like Guzman, Cuevas had difficulties keeping the ball down as he coaxed grounders just 26.3% of the time. While most other numbers looked decent (his FIP was just 3.03), Cuevas did perform against competition averaging 40 months younger. Based upon his age, Cuevas likely would begin the 2022 season with Kannapolis.
Jorge Ferrer
6´3´´
180 pounds
Age: 21
Shortly after signing an international contract in 2018 with the White Sox as a native of the Dominican Republic, Ferrer was assigned to the DSL squad. After pitching just two games and allowed nary an earned run, he was socked with a 72-game suspension for using Stanozolol, a steroid and performance-enhancing drug. This suspension essentially ended his 2018 season.
Ferrer was slowly worked into the DSL bullpen for the 2019, and for all intents and purposes, performed surprisingly well despite his rust. In seven outings totaling 9 2⁄3 innings, he posted a 2.79 ERA and 1.34 WHIP by allowing nine hits and four walks while striking out 10.
After missing the 2020 season due to the pandemic, he was converted from the bullpen to a starting role. Unfortunately for Ferrer, the results weren’t quite there for the young man. In 12 outings (eight starts), he compiled a 5.10 ERA and 1.73 WHIP. Spanning 30 innings, he relinquished 28 hits (.246 OBA) and 24 walks (7.2 BB/9) while striking out 42 (12.6 K/9). Based upon his results, Ferrer seemed more comfortable as a reliever (0.00 ERA, 1.00 WHIP, .111 OBA in eight innings) as opposed to his 22 innings as a starter (6.95 ERA, 2.00 WHIP, .288 OBA). Thus, if Ferrer does get promoted to Arizona or Kannapolis, it seems that he’d better suited for relief, where he gets righties and lefties out at a nearly identical clip.