Michael Wacha Is Evolving

Written by: Andrea Arcadipane (@scoutgirlreport)

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What do the Rays See in Michael Wacha?

In December, the Rays signed former Cardinals and Mets pitcher Michael Wacha to a one year, $3 million deal. While Wacha has never been an elite pitcher, his pitch mix does suggest that there is hope for him to improve his numbers moving forward.

After Wacha joined the Mets, he changed a couple of aspects of his game including:

  • Changing his release point
  • Eliminating the curveball from his pitch mix

With 2020 being such a small sample size (Wacha only pitched in eight games), it’s hard to tell how these changes will impact his future results. Using the 2020 numbers, however, can help give us an idea for what to expect with the Rays come 2021.

Wacha Changed His Release Point

After joining the Mets in 2020, Wacha changed his release point. Using the below graphics from Baseball Savant, we can see that his release point shifted down and further out from 2019 to 2020.

The red dashed line is included for reference and represents a fixed line at the 2-ft mark along the x-axis and the 6-ft mark along the y-axis.

How Did This Affect His Pitch Movement?

After Wacha adjusted his release point, there is more differentiation in terms of movement on his pitches.

In 2019, the movement of his cutter, four-seam, and change-up overlapped/blended together. To have more effective results, it would be better if the movement of the three pitches were better differentiated.

Wacha achieved the differentiation in movement in 2020, as we see now see a gap in movement between them thanks to the Savant Illustrator.

The landing spots for Wacha’s pitches also changed from 2019 to 2020. In 2020, Wacha threw more toward the east/west edges of the strike zone vs north/south in the years prior. I believe this is due in part to the updated release point, but also an intentional decision for Wacha to work more in the east/west horizontal plane of the plate.

Eliminating His Curveball

This idea of Wacha focusing on throwing along the east/west plane is reinforced by the elimination of his curveball, which is a pitch that moves along the north/south plane.

The curveball was Wacha’s worst pitch in terms of results, with an opponent SLG of .778 in 2019. He was throwing the curveball as the first pitch a lot of the time, but has since increased the use of a first pitch four-seam.

What Were the Results of These Changes in 2020?

Even though the sample size was small in 2020, it could be a sign of what’s to come for Wacha.

In 2020, his strikeout rate was a career high 23%, and his walk rate a career low 4.5%.

In terms of movement, there was an increase in both vertical and horizontal movement in all of Wacha’s pitches. The most substantial difference was in the vertical movement of his cutter, which was 4.7 inches more in 2020 than 2019.

Wacha threw a higher percentage of strikes with both his cutter and his change-up. His cutter had the biggest improvement, with an 8% increase in strikes thrown.

How did opposing hitters perform?

Even though increased movement and more strikes are nice, the actual results are the most important determination of the success of the changes.

When looking at opponent SLG, hitters did better against his four-seam and cutter in 2020, but worse against his change-up.

When looking at Whiff%, hitters swung and missed more against his four-seam in 2020, and about the same amount against his cutter and change-up.

One thing that is worth pointing out is that in 2020, Wacha’s FIP was less than his ERA by more than 1 run (which is a substantial difference). That implies that his defense last season may have contributed to the success of opposing hitters. Check out this article to better understand the differences between FIP and ERA.

His BABIP was also well above average, at .366, implying that he had some back luck last season and his numbers are expected to improve this year.

This idea of “bad luck” is reinforced when comparing his SLG to his xSLG for each of his pitches last season. (xSLG is a stat that attempts to eliminate defense by isolating factors the pitcher can control, such as exit velocity). The values for xSLG are significantly lower across the board, indicating that Wacha is not solely responsible for these high opponent SLG.

This paints a much better picture. While Wacha’s xSLG for 2020 is still higher than his SLG in 2019, at least it is in the same range.

What are the Rays going to do to further improve Wacha?

The Rays targeted Michael Wacha early on in the off-season and are excited about his addition to the team. The eagerness of the front office has a lot of Rays fans wondering what they plan to do with him to improve his results in 2021.

I think that the strategy for Wacha employed by the Mets was a step in the right direction. Eliminating Wacha’s weakest pitch, adjusting the release point to get better movement, and focusing on the east/west edges of the zone will give Wacha more of an advantage against hitters.

Even though opponents hit him well in 2020, it was only in 8 games. I wonder how different his numbers would have been if he had played a full season. Having the Rays defense behind him also will help significantly.

One change I can see the Rays propose for Wacha is to utilize the change-up more. Out of his three pitches, Wacha’s change-up has:

  • The highest whiff %
  • The lowest opponent SLG
  • The highest likelihood of being thrown for a strike

Either way, it will be interesting to see what adjustments Wacha makes heading into this season, and how they pay off over a larger sample size of starts.

Do you think Wacha has potential to improve this year?

Follow NEW P365 MLB Analyst Andrea Arcadipane on Twitter! @scoutgirlreport

Follow us on Twitter! @Prospects365

Graphs and statistics courtesy of Baseball Savant and FanGraphs

Featured image courtesy of the Tampa Bay Rays


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