O-Swing

 

In baseball, batters have to make decisions to swing or not. And, for a batter, it’s extremely important to know the strike zone and understand when to swing and when to take. If a batter can take a pitch off the plate, he is probably going to help his team do some good things such as drawing a walk.

However, some batters usually swing at pitches that are out of the strike zone.

Out of zone swing % ~2021.06.29
Player	O-Swing%
Salvador Perez	47%
Javier Baez	44.8%
Jose Iglesias	42.3%
Ryan Mountcastle	39.5%
Willi Castro	38.2%

Salvador Perez is having a good season so far, slashing .272/.301/.498. He’s not a patient hitter and loves to swing at pitches that are out of the strike zone. His chase rate is 47% and in his career, he never draws more than 22 walks in a single season. He has only 8 walks in 78 games so far.

Javier Baez is known as a free swing hitter and he’s not afraid of swinging at bad pitches. He doesn’t draw many walks, either. Baez drew 30 walks in 2017, which is his career high. His O-Swing% is nearly 45% and Baez is currently hitting .226/.271/.471 in 71 games.

Jose Iglesias had a great 2020. He slashed .373/.400/.556 and the Angels acquired him in the off-season. Iglesias’ batting average is .268 in 65 games. His O-Swing% was 34.4% in 2020 and this season, it goes up to 42.3%. Being more patient might be better for him?

In addition, Ryan Mountcastle’s chase rate is nearly 40%.

In the meantime, some players are patient and disciplined. They don’t like to swing at pitches that are out of the strike zone.

Out of zone swing % ~2021.06.29
Player	O-Swing%
Max Muncy	13%
Yasmani Grandal	14%
Trent Grisham	14.1%
Juan Soto	14.5%
Clint Frazier	15.1%

Max Muncy is one of the All-Star ballot finalists. After a disappointing 2020 season while hitting only .192, Muncy bounces back in 2021. By far, Muncy has an over .900 OPS. Muncy is very disciplined and he rarely swings at pitches that are out of the strike zone. He has a .418 OBP, leading the NL.

Yasmani Grandal’s batting average is only .180. However, his OBP is .391 and Grandal has drawn 59 walks so far, 2nd most in the majors. Grandal doesn’t chase very often and his O-Swing% is only 14%.

Trent Grisham and Juan Soto, ah. We might remember the story of the 2019 NL Wild Card game that changed two young players. Soto and the Nationals won the 2019 World Series. Trent Grisham was traded to the Padres. In this season, they are both very disciplined with a chase rate below 15%.

Furthermore, let’s look at percentage changes to see who’s less disciplined and who’s more disciplined.

Less disciplined? (O-Swing %, year to year changes) 2020~2021.06.29
Player	O-Swing% (+)
Kyle Seager	11.3% (+)
Sean Murphy	10.1% (+)
Jason Heyward	9.9% (+)
Brandon Lowe	9.3% (+)
Nick Solak	8.9% (+)

Kyle Seager’s O-Swing % is nearly 32% so far, but in 2020, his chase rate was only 20.6%. Kyle Seager’s K% increases from 13.3% to 26.2%. Also, Sean Murphy’s chase rate is increased by at least 10%. 

More disciplined? (O-Swing %, year to year changes) 2020~2021.06.29
Player	O-Swing% (-)
Carlos Correa	10.7% (-)
Jonathan Villar	10.1% (-)
Evan Longoria	9.3% (-)
Jose Altuve	8.5% (-)
Yuli Gurriel	8.5% (-)

Carlos Correa’s chase rate was 32.1% last year and this season, it’s below 22%. Correa is having a great season with a .300/.400/.529 slash line. Jonathan Villar drops his chase rate from 34.3% to 24.2%.

A hitter who often swings at pitches outside the strike zone doesn’t necessarily have bad outcomes. Salvador Perez is currently posting a .799 OPS. However, being patient and disciplined may be ideal for a hitter's long-term success. Evan Longoria has a bounce back season, batting .280/.376/.516 while having dropped his chase rate from 27.6% to 18.3%. Additionally, Max Muncy’s chase rate has been below 20% since 2016.