Zito’s curveball

In late December, I was just exploring if there’s something interesting on Twitter (X), well, I still call it Twitter. Of course, there were many rumors of trades or free agent signings on Twitter. However, suddenly, a highlight truly drew my attention. It was a highlight of Barry Zito’s curveballs.

 

Without doubt, in the video, those batters didn’t know what to do while seeing Zito’s devastating curveballs. Indeed, Zito’s curveballs look amazing in the video. While watching the highlight, I began to think about a question. How good was Zito’s curveball?

 

To understand a little bit more, I checked on the statcast website.

 

Player Comparison (Curveball, 2008~2015)
Player	Pitch%	BAA	Velocity (MPH)	Spin Rate (RPM)
Barry Zito	17.3%	.213	72.2	2737
Cliff Lee	8.5%	.177	75.4	N/A
Clayton Kershaw	12.6%	.121	74.0	2271

 

Zito made it into the big leagues in 2000 and won the AL Cy Young award in 2002. However, on the statcast website, we can only search for data 2008 onwards. There’s something missing, nonetheless, it could still help us to learn a little bit more.

 

From 2008 to 2015, Zito used his curveball more than 15% of the time. Opponents didn’t hit well against his curveball and batting average against Zito’s curveball was .213. During this period, the average velocity of Zito’s curveballs was 72.2 mph. He only tossed 3 games in 2015. The spin rate data has become available since 2015 and in 2015, the average spin rate of Zito’s curveballs was 2737 rpm.

 

Meanwhile, let’s take a quick look at 2 great left-handed pitchers, who are good at throwing curveballs and won the Cy Young award between 2008 and 2015. Firstly, Clayton Kershaw, made his MLB debut in 2008 and by far in his career, he already won the NL Cy Young award three times (2011, 2013 & 2014). Hence, it might be fair to say that his curveball is the best this generation. From 2008 to 2015, Kershaw used his curveball nearly 13% of the time. Hitting against Kershaw’s curveballs wasn’t easy. Opponents’ batting average was only .121 against Kershaw’s curveball during this period.

 

Additionally, Cliff Lee began his career in the majors in 2002 and his last game in the majors was in 2014. In 2008, he won the AL Cy Young award. From 2008 to 2014, Lee threw his curveball 8.5% of the time and opponents only batted .177 against his curveballs.

 

Swings and Misses (Curveball, 2008~2015)
Player	08	09	10	11	12	13	14	15
Barry Zito	14	47	56	19	66	45	N/A	3
Cliff Lee	34	30	31	56	58	45	7	N/A
Clayton Kershaw	43	38	14	28	58	75	62	121

 

Finally, let’s look at swings and misses. From 2008 to 2015, there were 4 times that Zito generated 40+ swings and misses via his curveballs in a single season. In particular, he created 66 whiffs in 2012 by using his curveball. Moreover, from 2008 to 2013, Cliff Lee’s curveballs generated at least 30 swings and misses each season. Now, let’s focus on Clayton Kershaw’s number. Kershaw’s curveballs only generated 14 swings and misses in 2010. However, in 2015, his curveball truly fooled MLB batters and created 100+ swings and misses.

There were ups and downs in Barry Zito’s career. He used to win the AL Cy Young award. He used to be left off the team’s playoff roster. Nonetheless, watching Zito’s curveballs is surely entertaining. Looking at the data from 2008 to 2015, we can see that opponents couldn’t hit well against his curveball and Zito was able to generate swings and misses by using his curveballs even though he wasn’t at his best during this period.