Will the Diamondbacks Have a Power Hitter Next Season?

Although trades and free agent acquisitions could change the answer, the keys to finding an answer are:

• Define ‘power hitter.’ For this article, the key measure is homers per plate appearance. Nevertheless, two other measures could help define a ‘power hitter:’ barrel %, and hard hit %. These measures can be found at Baseball Savant.
• Project how well the Diamondbacks will bat. Good projection systems reflect player skills and are understandable. Although there are many projections available, let’s look at a few projections that a baseball fan could find on-line.

How do a few projection systems differ?

Marcel is the simplest projection system. The MLB glossary wrote, “Despite the simplicity of its methods — it typically performs on par with other more complex systems.”

Actually, Marcel is the short name. The full name is “The Marcel the Monkey Forecasting System.”

Three strong points about Marcel follow:

• Transparency. The methodology is “totally open to the public.”
• If a player has very little data in the Majors, it projects close to the league average.
• Occam’s razer. It is the simplest explanation. Therefore it is more likely to be correct.

The Marcel method to project homers per plate appearance follows:

Tom Tango

Marcel projections for each player are provided at Baseball Reference.

Steamer was created by Jared Cross, a high school science teacher, with two of his former students, Dash Davidson and Peter Rosenbloom. Steamer resembles Marcel with three changes that add complexity.

• Instead of 5/4/3 weighted average, weights are set by regression analysis and are different for each statistic.
• The 1200 PAs (for regression to league average) may vary by statistic.
• It uses pitch tracking data to help forecast pitchers.

Steamer projections for each player can be found on the FanGraphs website.

ZiPS was created by Dan Szymborski. The long name is sZymborski Projection System. It starts with growth and decline curves based on player type. It fits 3 or 4 years of player data to a trend, factors in injuries, play-by-play data, and pitcher velocities to develop a projection.

ZiPS projections for each player can be found on the FanGraphs website. Also, it’s worth noting that FanGraph’s Depth Chart projection combines Steamer and ZiPS projections.

PECOTA stands for Player Empirical Comparison and Optimization Test Algorithm. It was developed by Nate Silver in 2003. After several minor changes, in February 2020 PECOTA was rebuilt “from the ground up.” It assumes that players with similar career paths will have similar trends in the future. Each statistic has its own “uncertainty range” and associated percentiles in that range.

PECOTA projections for each player can be found at Baseball Prospectus. My guess is that its batter projections for 2021 will be available in late January or early February.

A demarcation line for power hitters.

Let’s look at six hitters at the 80th percentile for hard hits, three from 2019 and three from 2020 (data from Baseball Savant).

• Mike Trout, 2019, 44.4% hard hit, 18.9% barrels, .075 HR/PA.
• Nick Markakis, 2019, 44.3% hard hit, 3.0% barrels, .019 HR/PA.
• Jackie Bradley Jr., 2019, 44.5% hard hit, 9.6% barrels, .037 HR/PA.
• JD Davis, 2020, 45.2% hard hit, 8.9% barrels, .026 HR/PA.
• Evan Longoria, 2020, 45.2% hard hit, 11.5% barrels, .033 HR/PA.
• Chris Taylor, 2020, 45.0% hard hit, 11.5% barrels, .037 HR/PA.

For these 6 players, the average HR/PA is .038. That average will be a demarcation line. At the line or above is a power hitter. Below that line is not.

Projections of homers per plate appearance.

For Diamondback position players, let’s look at the Marcel, Steamer, and ZiPS projections. The average of the three projections was compared to the demarcation line for power hitters. Projected power hitters are shaded green, borderline power hitters are shaded yellow.

Data from Baseball Reference and FanGraphs.

Addendum on 30 December.

The previous table was updated (updated table follows):

• added more recent 2021 ZiPS projections.
• added Seth Beer, Trayce Thompson, and Alek Thomas.
• Beer and Thomas Steamer estimates were based on Steamer’s SLG and ISO projections.

The impacts of the update:

• Kole Calhoun bumped Christian Walker out of the top spot.
• Seth Beer joined the power hitters.
• Eduardo Escobar dropped to borderline power hitters.
• Andy Young and Daulton Varsho were dropped from the borderline power hitters.

Data from Baseball Reference and FanGraphs.

The answer to the question is yes.

Three Diamondbacks are projected to be power hitters: Christian Walker, Kole Calhoun, and Seth Beer. In addition, two Diamondbacks are projected to be borderline power hitters: Eduardo Escobar and Carson Kelly.

It would not be surprising for many Diamondback hitters to outperform their projections. Four examples follow.

• Christian Walker’s hit tool is comparable to the best in the Majors (source article).
• As 24 year old Daulton Varsho adjusts to the Majors (first 115 PAs in 2020), likely he will exceed projections.
• If Andy Young, with only 34 plate appearances in the Majors, performs at the level of the updated ZiPS projection, he would join the power hitters.
• Marcel projected Kole Calhoun’s HR/PA at .047 despite its age adjustment. Although he is 33 years old, there is good reason to think he will hit better than an aging curve might suggest.