Steven Matz Needs a Repeatable Motion

I was as excited as any Mets fan when Steven Matz made his major league debut on June 28, 2015. Only 24 years old, the young left-hander stymied the Cincinnati Reds, limiting them to two runs in 7.2 innings, and while the TV cameras kept cutting to family in the stands at Citi Field, Matz went 3-for-3 with the bat, driving in four runs.

He looked like a future ace to me and even my wife felt he “was easy on the eyes.”

After his debut, Matz missed several months with a lats muscle tear, returned and then missed a few starts due to a blister, and in September had back discomfort and spasms. Still, by the end of the season he was a perfect 4-0 with an ERA of only 2.27. In the playoffs, Matz limited the Cubs to one run in 4.2 innings and surrendered only two runs in five innings against the Royals in the World Series.

The future certainly looked “easy on the eyes.”

However, in 2016 and 2017, Matz struggled to a combined record of 11 wins against 15 losses, and his ERA over the two seasons was 4.30. His 2016 season ended early due to a should impingement and surgery to remove a bone spur in his left elbow. In 2017, Matz went on the disabled list with a flexor strain in May and, in August, he underwent surgery after being diagnosed with irritation of the ulnar nerve.

While bad luck or bad genes could be to blame for his series of injuries, perhaps the fault lies more with both Matz himself as well as Mets player development and pitching staff personnel.  Thanks to publicly available data on, Mets fans can see that Matz has never really had consistent, repeatable mechanics.

Inconsistency is one of the biggest variables in pitching. Without a repeatable delivery, a pitcher won’t be consistent.

In addition, good mechanics are definitely a form of injury prevention as the same muscles are being worked in the same way and tendons are stretched in the same manner. A pitcher with consistent mechanics won’t tire as easily as one without them, as they are using their whole body and can usually go deeper into games, as their muscles and tendons build up strength and flexibility from repeated use.

For his career to-date, Matz has averaged less than 5.2 inning per start.

Below is a chart from that demonstrates how consistently inconsistent Matz has been on the delivery of his most frequent used pitch, the sinking fastball.  Note, whether month-to-month or year-to-year, Matz has been unable to deliver his fastball from the same spot two months in a row.


Wonder about his other pitches?  Here is a graph showing that his slider is a bit better, but far from ideal:

Note that during 2016, Matz’s slider was released much higher than in 2015, but in 2017 after one month of pitching, he had four months wherein he released his slider within a one inch vertical window. However last season he started out with the lowest release point of his career, and never reached even the lowest release point he had in 2016.

Wonder about his curve? Well, the graph below paints a more worrying picture:

Note that each line represents .4 feet, or about four inches. Throughout his Major League career, Matz has varied the release point of his curve from month-to-month and from season-to-season by multiple inches.

Mets fans old enough to wince at the memory of the Scott Kazmir for Victor Zambrano trade will recall that Zambrano’s problem was not the velocity of his pitches, or the break on his slider. Despite one pitching coach promising to fix Zambrano’s mechanical problems “within 10 minutes,” Zambrano suffered from inconsistent mechanics that hurt his control, drove up pitch counts and forced many short starts.

After three seasons with the Mets, Zambrano was released after going a combined 10-14 with an ERA of 4.42. One season later, he was out of baseball.

Current Mets fans certainly hope that Steven Matz does not become the next Victor Zambrano. All Mets fans hope that this season’s starting pitching is “easy on the eyes.”

About Carl Aridas 37 Articles
Mets fan since the Wayne Garrett/Craig Swan/Joe Torre days, Carl works as a bank consultant during the day, but at night enjoys writing baseball articles for Fangraphs, Hardball Times, and Metsmerized Online. He joined as a MMO Rookie of the Year hopeful in 2016 and has been a Mets fan for more than 40+ years.