Series Preview # 15 : Diamondbacks vs Dodgers

This season’s Diamondbacks showed they are better than pre-season expectations. They won their first series with the Dodgers. They were swept their second series with the Dodgers. Truly, their third series with the Dodgers is unpredictable. Let’s step back to see a new perspective.

“You’ve got to be adaptable and do things in a very uncommon way. You can’t accept the norm and we wont. We wont go out there and give anything less than our best effort.” — Torey Lovullo

Our question is different but similar to Curly’s question in City Slickers, “Do you know what the secret to this series is?” Our answer is the same, “… One Thing. Just one thing. You stick to that and the rest don’t mean shit.”

The balance of this series will be tipped by one thing: pitching. More specifically, it will be tipped by which team has the better starters and which team has the better bullpen.

Let’s compare the projected starters and compare the bullpens.

Comparing the Starters.

For each of the starting pitchers in my projected matchups, let’s only look at their games between the Dodgers and the Diamondbacks, when those games happened between March 2019 and 24 May 2022. The projected matchups follow:

• Thursday 6:40 PM: Arizona time: Ryan Pepiot vs Humberto Castellanos.
• Friday: Tony Gonsolin vs Madison Bumgarner.
• Saturday: Tyler Anderson vs Merrill Kelly.
• Sunday: Walker Beuhler vs Zack Davies (contingent on status of shin contusion, perhaps Zac Gallen will pitch Sunday).

In games between the two teams, the starter’s games were ranked by each game’s ERA (earned runs times 9 divided by innings pitched). Using that ranking, the median game was selected to represent that pitcher (for Gallen the midpoint of two middle games). Median game comparisons follows:

• Ryan Pepiot 3 ERs in 4.0 innings vs Humberto Castellanos 3 ERs in 5.0 innings. This matchup gives a slight edge to the Diamondbacks. A caveat is small sample size because there was one game each for Pepiot and for Castellanos.
• Tony Gonsolin 2 ERs in 6.0 innings vs Madison Bumgarner 2 ERs in 5.0 innings. This matchup gives a slight edge to the Dodgers.
• Tyler Anderson 3 ERs in 6.0 innings vs Merrill Kelly 3 ERs in 6.0 innings. This matchup is equal.
• Walker Beuhler 1 ER in 8.0 innings vs Zack Davies 2 ERs in 7.0 innings or Zac Gallen 1.5 ERs in 5.2 innings. This matchup gives an edge to the Dodgers.

The following table shows the general distribution of ERAs for the 9 pitchers.

2019 through 24 May 2022. Distribution of ERAs for Diamondback-Dodgers games. Data from Baseball Reference.

My view is that the first three games of the series will likely be decided by the bullpen. If Walker Beuhler pitches very well, the bullpen will matter less in the last game.

Comparing the Bullpens.

For each reliever, let’s only look at their games in 2022. Let’s exclude all pitchers with less than 5 relief appearances in 2022. The important measures are Got-The-Job-Done percentage (GTJD%) (no earned runs and no inherited runners scored) and percentage of Broken Goose Eggs (BE%) (Broken Goose Eggs divided by possible eggs (sum of broken and unbroken, but excluding ‘meh’ eggs). The definition of Goose Eggs can be found in this Nate Silver article.

My view is that the demarcation lines between reliable pitchers and an unreliable pitchers are 67.7% Got-The-Job-Done and 30% Broken Eggs. For details, see this AZ Snake Pit article.

The following two tables show the Diamondbacks have the better bullpen for the following reasons:

• Diamondbacks have the top three relievers (Joe Mantiply, Kyle Nelson, and Noe Ramirez). Another plus is that Mantiply and Ramirez had broken egg percentages less than 30%.
• Looking beyond the broken egg percentages, the Diamondbacks earned more goose eggs than the Dodgers (31 vs 13). Mantiply earned 6 goose eggs, Melancon earned 9 goose eggs, and Kennedy earned 10 goose eggs. The most goose eggs earned by any Dodger reliever was 6 by Hudson.
• The Diamondbacks and the Dodgers have reliable closers. Kimbrel has a slight edge in got-the-job-done (76.9% vs 70.6%), while Melancon earned a lot more goose eggs (9 vs 2).

2022 season, games through 22 May. Excludes relievers with less than 5 appearances. Data from Baseball Reference. Note that Poppen is light green because on 23 May he raised his GTJD% to 70%, which would be dark green.

The following table ranks the reliable relievers by the got-the-job-done percentage.

2022 Season through 22 May. Data from Baseball Reference.

Summary & Wisdom.

The starting pitchers are roughly evenly matched for the first three games of the series. The bullpens are likely to tip the balance in the series. Based on got-the-job-done and goose eggs earned, the Diamondbacks’ bullpen is better, which will likely translate to a Diamondbacks’ series split or series win.

Widely used baseball statistics indicate that the Dodgers are the better team. As you know, baseball is more than statistics. This series is an asymmetric challenge that is likely to benefit the Diamondbacks. One Diamondback win would be good, considering the Dodgers’ overall talent. Splitting the four game series would greatly uplift the Diamondbacks. More than uplifted, baseball people would notice that this season’s Diamondbacks are playing excellent baseball.

“Numbers, to me, it’s like a bikini — it’s a lot, but it doesn’t show everything,” — Torey Lovullo