“Deep Dive” focuses on the depth of each position in the Chicago White Sox organization. The relievers will be written up in five parts:
- Depth in the lowest levels (Dominican through Great Falls)
- Depth in Class A (Kannapolis and Winston-Salem)
- Depth in the highest levels (Birmingham and Charlotte)
- Under the Radar-type detail on one of the White Sox players at that position
- Free-agent options at that position, plus sneak peeks into available players in the upcoming 2019 MLB draft
While many of the top southpaw relief prospects finished the season with Winston-Salem or higher, Single-A overall was ripe with promising southpaws. The players’ ages listed below are as of April 1, 2019.
Kubat’s four-year career with Nebraska was spent primarily as a starting pitcher, and he fared reasonably well despite not flashing any power numbers. His senior season was a microcosm of his college years, as he posted a 2.97 ERA and 1.24 WHIP in 94 innings, surrendering 102 hits and 15 walks while fanning 63. Kubat went undrafted in 2015, but signed with the Kansas City Royals shortly afterward. The White Sox acquired Kubat for cash prior to the 2017 season, and the southpaw has been pretty much lights-out since.
Of course, with the caveat that ERA and WHIP don’t always tell the full story for a reliever, Kubat’s 2017 season spanning Kannapolis, Winston-Salem and Birmingham was nevertheless outstanding. In 74 2⁄3 innings over 35 games (three starts), Kubat allowed just 50 hits and 12 walks against 77 strikeouts for a 1.69 ERA, 0.83 WHIP and 26.5 K%, while allowing just two home runs. When just focusing in on his seven-game stint in Birmingham last year, Kubat posted a 1.30 ERA and 0.65 WHIP by allowing just 10 hits (.141 OBA) and two walks (2.7%) while striking out 17 (23.0%) in 20 innings.
Despite his gaudy stats with the Barons, Kubat began the 2018 season in Winston-Salem. not Birmingham. Kubat posted solid numbers again this year for the Dash, although he wasn’t quite as spectacular: 3.55 ERA and 1.02 WHIP over 91 1⁄3 innings, allowing 97 hits (.279 OBA) and 13 walks (3.5%) as opposed to 77 strikeouts (20.7%). Kubat actually started nine games for the Dash, and didn’t fare well. Strictly looking at Kubat’s relief work, his numbers would’ve again been outstanding: 2.06 ERA, 0.98 WHIP, .230 OBA, with seven walks and 42 strikeouts in 48 innings.
Because Kubat doesn’t throw particularly hard (his repertoire includes an upper-80s fastball, slider and changeup), the White Sox consider him primarily as organizational depth. However, with Kubat’s tremendous control and command, he’s been able to outperform his stuff thus far in his pro career. Kubat will be eligible for this year’s Rule 5 draft, but is unlikely to be selected due to his age and limited work beyond A+ ball. Kubat likely will begin next season with Birmingham.
Schryver, a Mechanicsburg, Pa. native, had a respectable run as starting pitcher (despite a 13-23 record) for Villanova from 2014-17, where he struck out 249 hitters over 277 1⁄3innings of work (20.6%). His results were solid but unexceptional for the Wildcats, as he compiled a 3.57 ERA, 1.36 WHIP, .249 OBA and 122 walks (10.1%) during his four-year stint.
Schryver’s senior season was arguably his best despite an increase in walks, as he posted a 2.44 ERA, 1.26 WHIP, .213 OBA, 11.8 BB%, 29.0 K% and no homers allowed. Others seemed to agree, as Schryver was named to the All-Big East team as a result of his efforts. The Tampa Bay Rays selected him in the seventh round of the 2017 MLB draft, and immediately converted the lefty to a bullpen role.
Schryver instantly took to his new opportunity, and threw many more strikes out of the pen. His first team was the Hudson Valley Renegades, the Rays New York-Penn League short-season affiliate. In 20 outings encompassing 34 1⁄3 innings, Schryver posted a 3.12 ERA and 1.15 WHIP by allowing 35 hits (.252 OBA) and just five walks (3.4 BB%), while striking out 38 (26.0 K%). For an encore in 2018, Schryver combined with Bowling Green (A) and Charlotte (A+) for a 2.40 ERA and 1.07 WHIP while surrendering just 38 hits (.212 OBA) and 14 walks (7.0 BB%); he also punched out 59 hitters in the process (29.5%).
The White Sox traded international signing bonus pool money for Schryver on July 31, just two days after receiving higher-profile southpaw Caleb Frare from the New York Yankees in a similar deal. In 15 innings over nine appearances for the Dash, Schryver continued to build upon his success, with a miniscule 1.20 ERA, 0.80 WHIP, .170 OBA (nine hits), 5.1 BB% (three walks), and 35.6 K% (21 strikeouts). This obviously was a small sample size, but was quite encouraging nonetheless.
According to Baseball America, Schryver owns a fastball that mostly runs 88-91 mph but has been clocked as high as 93. Other pitches in his repertoire include a spike curveball (often called a knuckle curve, which former hurlers Mike Mussina and Cliff Lee successfully deployed) and a changeup. Schryver hasn’t been treated as a LOOGY, and for good reason — righties hit him slightly worse this year (.201) than lefties (.205), which points to the effectiveness of his change. Schryver’s career GO/AO ratio of 1.68 is terrific, and is largely a testament of the effectiveness of his spike curve and his ability to keep fastballs down. This ratio would be ideal for a bandbox like Guaranteed Rate Field. My expectation is for Schryver to begin next season with Double-A Birmingham.
Sousa, a resident of North Palm Beach, Fla. pitched all four of his collegiate seasons with the Virginia Cavaliers, where all but three of his 70 appearances were out of the bullpen. His best season was his junior year (2017), when he had a 4.09 ERA and 1.21 WHIP over 33 innings, allowing 25 hits and 15 walks while striking out 44. The Washington Nationals selected him in the 34th round of the draft, but Sousa elected not to sign.
In 2018 Sousa struggled, to the tune of a 5.23 ERA and 1.35 WHIP over 43 innings, allowing 36 hits and 22 walks while striking out 61. His overall college numbers, with the exception of strikeouts, wasn’t been all that jaw-dropping: 5.50 ERA and 1.55 WHIP, while allowing 98 hits, 69 walks, and 130 strikeouts over 108 innings of work. Despite these numbers, the White Sox liked what they saw and drafted him in June.
Sousa dominated in a brief nine-game stint in the hitter-friendly Pioneer League, where he allowed just four hits (.089 OBA) without a walk, 18 strikeouts, earning two saves for Great Falls over 13 innings of work. This led to an incredible 0.00 ERA and 0.31 WHIP, along with a phenomenal strikeout rate of 40%.
Sousa earned his promotion to Kannapolis on July 15, and while his production hasn’t been nearly as dominant, the southpaw was very solid overall. In 22 1⁄3 innings over 11 appearances, Sousa compiled a 2.01 ERA and 1.21 WHIP, while allowing 20 hits (.256 OBA), seven walks (7.9 BB%), 24 punchouts (27.0 K%), and earning two saves. Thus, through August 30, his combined totals for 2018 with Great Falls and Kannapolis were: 1.27 ERA, 0.88 WHIP, 35 1⁄3 innings, 24 hits (.195 OBA), seven walks (5.2 BB%), 42 strikeouts (31.8 3%), and six saves. Not too shabby!
Sousa features an impressive three-pitch repertoire. His fastball maxes out at 94 mph but generally runs 89-92, according to Baseball Draft Report, and has low, hard, tailing action when down in the zone — a heavy pitch, when located correctly. Secondly, Sousa offers a mid-80s slider, with hard spin and downward bite. His third pitch is a changeup with nice, diving action, which he primarily uses against right-handed hitters. Righties batted .225 against Sousa’s offerings this year, while lefties hit a paltry .065.
The big thing with Sousa is not his stuff, but his control. A big reason for his problems with Virginia was that fell behind the count constantly, which led to higher walks and more pitches the hitters were able to see.
Sousa pitched 31 2⁄3 innings over 18 games, so the White Sox aren’t treating him as a LOOGY quite yet. With his success and his age (he turns 24 next April), he should begin next season with Winston-Salem and earn a promotion to Birmingham by June. While righties have hit just .247 against Sousa overall, they fared better against him at Kannapolis, to the tune of a .327 average. If Sousa can successfully locate his changeup and stay ahead on righties, he could be quite a successful multiple-inning southpaw option out of the bullpen — something similar to Jace Fry. If not, his floor would still be that of LOOGY; after all, an OBA of .065 versus lefties is nothing to sneeze at.
Perez, a native of Orlando, dominated his senior season with Timber Creek H.S., to the tune of a 1.95 ERA and 112 strikeouts in 51 2⁄3 innings. Staying in-state to pitch for the University of South Florida, he struggled to adjust to a bullpen role for the Bulls, as he posted a 6.75 ERA and 1.89 ERA — allowing 26 walks and 32 hits in his 30 2⁄3 innings of work. However, Perez rebounded well in his sophomore and junior seasons, throwing more strikes. Over his final two years, Perez improved his ERA to 2.53 and WHIP 1.13 by allowing just 62 hits and 30 walks over his 81 2⁄3 innings, striking out 102 hitters and saving 18.
Due in part to these improvements, in addition to a spike in velocity, the White Sox selected him in the eighth round of the 2018 MLB draft. Perez made quick work of Pioneer League hitters in his four-game stint with Great Falls by posting a 1.42 ERA and 0.47 WHIP in 6 1⁄3 innings of work, allowing just three hits (.136 OBA) and no walks while striking out seven (31.8%).
Perez was promoted to Kannapolis on June 29, where he was 1.9 years younger than league average. In 16 games totaling 25 innings for the Intimidators, the lefty posted a respectable 2.88 ERA and 1.36 WHIP in allowing 21 hits (.233 OBA) and walking 13 hitters (11.7%) while striking out 24 (21.6%). Perez may have been battling fatigue with Kannapolis — his 2018 innings between college and professional surpassed his two previous years combined — causing him to lose a bit of control as a result.
Perez’s fastball, which was up to 90 mph during his prep days, spiked to the mid 90s by the time he was a college junior. His repertoire also includes a nifty 11-5 curveball which he’s managed to keep down, and a fringy changeup which can improve if he improves his arm speed. Perez has a low-effort, three-quarter delivery which makes him difficult for lefties to pick up. He hasn’t been treated as a LOOGY to date, as he pitched 31 1⁄3 innings during his combined 20 games with Great Falls and Kannapolis. Lefties batted just .184 against his offerings, while righties fared a bit better at .230, which still isn’t too shabby.
If Perez can improve upon his changeup, he could have high-leverage potential. Like Sousa, anticipate him beginning next season with Winston-Salem. However, the White Sox may decide to take things slowly with Perez due to his age; if that’s the case, he’ll return to Kannapolis.
Escorcia, like fellow former White Sox lefty Jose Quintana, is a hurler hailing from Colombia. After signing a minor league contract with the Sox on Jan. 28, 2013, his first two seasons were spent in the Dominican League, where Escoria did exceptionally well. Combining for 99 2⁄3 innings for the DSL in 2013 and 2014, he posted a 1.90 ERA and 1.00 WHIP as he allowed just 70 hits (.202 OBA) and 30 walks (7.7%) while striking out 109 (28.1%).
Escorcia struggled in 2015 with the AZL White Sox, which perhaps had as much to do with learning a new culture than anything else. That year for the AZL Sox in 35 innings, he compiled an uncharacteristic 6.17 ERA and 1.77 WHIP in surrendering 48 hits (.331 OBA) and 14 walks (8.62%) while fanning 34 (21.0%). Despite fighting his control, Escorcia had a much better season in 2016 with Great Falls, as he posted a 4.06 ERA and 1.37 WHIP in that difficult pitching environment; in his 24 1⁄3 innings for the Voyagers, he relinquished 15 hits (.176 OBA) but 18 walks (17.0%) while punching out 27 batters (25.5%).
Although Escorcia posted a solid year with Kannapolis in 2017, he returned to the Intimidators this past season and posted better results, with a 2.66 ERA and 1.32 WHIP over 44 innings — allowing 39 hits (.238 OBA) and 19 walks (10.1%) while striking out 62 (33.0%).
Escorcia’s repertoire includes an upper 80s-low 90s fastball which has some sinking action, a 79-80 mph slider with nice breaking action and a plus mid-70s curveball that is a knee-buckler. Lefties hit .262 against his offerings this year, while righties hit just .223, so Escorcia really doesn’t have a LOOGY profile. His GO/AO ratio for his career is 1.47, which is a testament to the quality of his sinking fastball, while his 28.3% career whiff rate speaks to the quality of his curve and slider.
Escorcia is eligible for this year’s Rule 5 draft, but likely won’t be selected because he’s never advanced past Kannapolis. That should change in 2019, however, with an assignment to Winston-Salem.
After a respectable first three years with Michigan State, Mockbee picked a bad time to have his worst season in college. In 29 games for the Spartans as a senior, totaling 43 2⁄3 innings, he posted a 5.15 ERA and 1.65 WHIP by allowing 50 hits and 22 walks while fanning 56. Based more on the strength of his previous years (including decent strikeout numbers) and the fact that he’s a southpaw, the White Sox selected Mockbee in the 29th round in 2017.
While his ERA was a respectable 3.18 with Great Falls after the draft, all the other numbers told a different story. For the Voyagers in 20 games totaling 28 1⁄3 innings, Mockbee compiled a high 1.59 WHIP, as he allowed 28 hits (.250 OBA) and 17 walks (12.9%) while striking out 22 (16.7%).
In 11 games for Winston-Salem and Kannapolis in 2018, Mockbee provided better results. In a combined 13 1⁄3 innings, he posted a 3.38 ERA and 1.05 WHIP by surrendering just eight hits (.170 OBA) and six walks (10.9%) as opposed to 11 strikeouts (20.0%). Unfortunately, he hit the DL on July 20, and never returned.
There is some hope for Mockbee as a prospect, as he allowed lefties to hit .143 and righties just .182 against his offerings. However, it’s likely that the three guys above have passed him up on the depth chart. If healthy, Mockbee likely will return to Kannapolis to begin 2019.
Few teams can provide the bullpen depth that the White Sox presently offer, especially when you review the southpaws that also finished with Kannapolis like Sousa, Perez and Escorcia. The minor league depth guys like Kubat aren’t too shabby either. With all this depth, it’d be safe to assume that some of these arms could be available to trade when the team’s contention window eventually arrives.