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Right and Wrong: Luis Castillo’s 2021 Fantasy Outlook

Welcome back to another article! What an amazing World Series match up we have! We have the Rays and the Dodgers who both were the #1 seeds in their respective leagues. Both these teams provide tons of great pitching, defense, clutch hitting, and storylines galore. While it’s been a treat watching nearly every playoff game that I possibly can so far, I’m very excited to be looking ahead to next season. In a season in which a global pandemic was occurring and we only had 60 games of data, it is incredibly hard to make assessments about players and their performances, and that includes Luis Castillo, who I’ll be looking at in this article.

As with many sports, there are many factors that come into play when looking at how a player performed during a particular season. Players may be statistically slow starters, not play well in certain weather, have problems with certain teams that they continued to face in the re-alignment, and more. What a player has done in their career before 2020 needs to be taken into consideration for these exact reasons.

This offseason, I’ll be doing a series of articles looking at what went right, what went wrong, and the overall 2021 outlook for certain players. I can only take into account the data that has been given and use that to best assess what to expect from them next season. This should be fun! Let’s dive into our next player in this series: Luis Castillo.

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What Went Right for Luis Castillo in 2020

Change Up Stayed Elite

The first thing that comes to my mind when I hear “Luis Castillo” is his silly-good change up. I don’t know if that’s an expression but it is now. Luis Castillo has had one of the filthiest changes in the game for a few seasons now, and it remained so in 2020. While it wasn’t quite the 2019 version, it still posted a .170 xBA and a .270 xSLG. He maintained a 40%+ whiff rate and continued a low velocity and launch angle off of this pitch. It remains his favorite pitch as he again used in 30% or more of the time and if it continues remaining this effective, Castillo should continue to produce Ace-like results with it.

X-Stats Show Likely Positive Regression

If there was a poster boy for someone who might have suffered bad luck and his stats should have looked better, it might be Luis Castillo. While expected stats don’t always paint the full picture, it gives us as analysts a good idea of if someone overperformed or underperformed their numbers.

Castillo is a very good example of someone who might have been better if the season had continued progressing. Castillo finished with a very good 3.21 ERA. He had an expected ERA of 3.04. His expected batting averages on his two top pitches (the fastball and the change) were both at least 35 points lower than the actual batting averages. 88 points on the slugging differences as well. His xFIP (Fielding Independent Pitching) which is one of the top metrics for looking at exactly how well a pitcher is pitching minus their defense, was 2.82. All in all, Castillo was much better than his final numbers indicated.

Strikeout and Walk Rates 

When looking at a pitcher’s development, there are two things that are important to look at. One is that they are fooling hitters to get more swings and misses and to not put the ball in play as much. The other is to limit putting men on base with free passes. Luis Castillo has made strides each year raising his strikeouts while dropping his walk rate. Luis Castillo upped his strikeout percentage to a career-high 30.5% in 2020, while recording the second-lowest walk rate of his career at 8.2%. His K’s per 9 jumped up to over 11 per 9 for the first time in his career and his walks at barely over 3 per 9. This allowed for Castillo to have a career-best 3.71 K/BB ratio and looks to continue getting better with his command of the strike zone while fooling hitters at the plate.

Flyball/Groundball Percentages

Besides the walks and strikeouts, another big part of a pitcher’s development is to try and limit the balls in the air and induce weaker contact with balls being put on the ground. Luis Castillo again continued this trend in the right direction in 2020. For the third consecutive year, Castillo dipped his flyball rate from over 20% to under 15% and upped his groundball rate from 48% to 58%.

How does this correlate? His ERAs over the last 3 seasons are: 4.30, 3.40, and 3.21. The combination of Luis Castillo getting more strikeouts as listed above, and getting higher ground ball rates, are positively impacting his ERA and getting Castillo closer to an ace tier.


What Went Wrong

Allowed Harder Contact

Let me start off by saying, there’s not a lot Castillo needs to improve on based on his progress from 2019 to 2020. There are a few items I will nitpick just for the fact that no pitcher is perfect. The first is the type of contact that Castillo was giving up. Luis Castillo’s solid contact % on balls put in play nearly doubled from the previous year. Castillo also had a 3.5% jump in his hard contact percentage and all could have contributed to a potential higher earned run average if not for a 70% of base runners left on base.

Sinker Still Needs Work

If this was one of the pitches Luis Castillo barely threw, this would not be on here. However, according to Statcast, he threw this pitch over 25% of the time or a 4.5% increase from 2019. The results on this pitch are not encouraging as he has had an expected batting average of over .290 on this pitch in each of the last two seasons.

The hitters are not being fooled by this sinker as much as the rest of his arsenal. I would love to see the usage flip flop with his slider, as it produced a much better .162 xBA this year and was still thrown almost 18% of his offerings. Hitters seeing his sinker less could make it more effective while upping the use of another great weapon.

Outlook for 2021

Luis Castillo may not be drafted like the ace of a staff all the time, but he deserves to be. As stated prior in this article, Castillo outperformed his actual numbers this season and could come at a little more of a discount because of what the back of his baseball card would say. When people ask how to spot players to outperform their ADP in drafts or give a great investment on return, Castillo is that type of player as he has top-10 pitcher upside, if not greater in my opinion.

Castillo continues to make great strides in becoming an all-around pitcher. One that will provide you strikeouts, limit walks, go deep into games, and keep the ball in the yard. Keeping the ball in the ballpark was one thing that was not mentioned prior and Castillo has also excelled at this as he had a launch angle of 2.2 degrees and his HR/9 rate dip each of the last 3 seasons to now a career-low at 0.64.

Luis Castillo should be that pitcher that you can feel amazing about if he’s your SP2 or should feel really good about if he’s your SP1 if you decide to grab hitting with your first couple of draft picks. Expect ace-like production and great ratios from “La Piedra” next year.

Wondering which breakout pitchers our FantraxHQ staff are not buying into? Check out our “Staff Roundtable” for in-depth analysis of those pitchers.

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