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Starting pitching was a major strength for the Cincinnati Reds in 2019 after being a major weakness in the previous two seasons. A large portion of that success in 2019 can be attributed to two pitchers, Luis Castillo and Sonny Gray.
Though not reflected in their 2019 ERA, Castillo and Gray actually had similar seasons.
The same similarities seem to carry over into 2020 projections. ZiPS projects Castillo to have a better season in 2020, with a projected 3.59 ERA/3.63 FIP, to Gray’s 3.82 ERA/3.78 FIP. Again, ZiPS echoes the sentiment that the two are very similar pitchers, as evidenced by the very small differences across the board in stats such as K%, BB%, HR/9 and BABIP. ZiPS also lists a former player that’s most comparable to each player’s projections, and interestingly, the top comp for both Gray and Castillo was Ken Hill. The biggest difference between the two is strikeout rate, in which Castillo has a notable edge.
While those stats seem to indicate that the two are similar pitchers, the general public sentiment is much different between the two players. Castillo is seen as young and exciting, while there is much less hype around Gray. Castillo is going into his age 27 season, while Gray is going into his age 30 season, and that could be the difference in public perception. While 30 is not old by any means, Castillo is considered to be closer to being in his prime than Gray.
At the same time, Gray does also have one major advantage over Castillo, his track record. Gray has now posted four full seasons, plus a partial rookie season, with an ERA+ above 120. Castillo just has one such season, plus a partial rookie season as well. Some, however, are soured by Gray’s poor 2018 season in New York, though his FIP (4.17), xFIP (4.10) and SIERA (4.28) indicated he was in fact an above average pitcher.
While stats do indicate major similarities between Castillo and Gray, the pitchers get there in different ways. Gray relies on a curveball and a slider as his two put-away pitches, while Castillo’s changeup is his best pitch. Castillo is more of a power pitcher than Gray, with a fastball averaging over 96 MPH, while Gray averages around 93 MPH.
Some interesting insights can also be pulled from their batted ball profiles. The two have similar BABIP and almost identical line drive and infield fly percentages. Additionally, according to Fangraphs, their soft, medium, and hard hit rates were nearly identical. Castillo, however, is more ground ball heavy than Gray, though both could be classified as ground ball pitchers.
It is also notable that Gray generated significantly more pull contact. That could be because of his lesser fastball velocity compared to Castillo, though it’s also interesting that Gray also has the higher percentage of contact to the opposite field.
More difference between Castillo and Gray can be seen in their contact profiles. Gray throws more pitches in the zone and is less effective at getting hitters to chase. Gray also gives up more contact, both in the zone and outside the zone, which makes sense considering his lower strikeout rate. Notably, Castillo gets a higher percentage of swings from hitters, both in and out of the zone. This is reflected when looking at their strikeouts. Castillo struck out 223 hitters in 2019, and only 22 of them were strikeouts looking, while 49 of Gray’s 203 strikeouts were looking. For their careers, Gray gets 20.8% of his strikeouts looking, while Castillo gets just 12.7%.
Disagreements about which pitchers are aces make for great arguments. Are aces simply the best pitcher on each team? In that case, who is the Reds’ ace, Luis Castillo or Sonny Gray? Are aces the top 30 pitchers in the game, one for each team? In that case, the Reds have not one, but a pair. Just as in poker, that’s a great place to start.
[Featured images: https://twitter.com/Reds/status/1149736445290196994; https://twitter.com/Reds/status/1143552512089370624]
Editors: Please welcome Kyle Berger, one of our new writers!
