Plate Appearances With Runner(s) on Base

Does a runner on third base impact wOBA or add positive plate appearances?

Definitions for this question:

— wOBA is the weighted on base average with weights based on theoretical impacts on scoring runs.

— Positive plate appearances: hits, walks (BBs), hit-by-pitch (HBPs), and batter out PAs with positive RE-24. No weights were applied.

With one out and runners on base, the Diamondbacks had a high percentage of positive plate experiences and a high wOBA. Also, with one out and runners on base including third base, the strikeout rate was lower and the balls in play were higher. The details are shown in the following table. Note that RoB means runners on base.

2022 Diamondbacks. Data from Baseball Savant.

Let’s look at what situations stand out in terms of strikeouts, hits, walks, and positive PAs/wOBA.

Strikeouts. With a runner on third base, strike outs are bad. If it’s the third out, the opportunity is lost. If it is the second out, sacrifice flies and fielder’s choices are taken off the table. Even if it’s the first out, it uplifts the spirit of the other team’s pitcher.

With one out and a runner on third base, to their credit Diamondbacks batters struck out about half as much as average. It appears those non-strikeouts became balls-in-play.

Hits. Hit’s with runners on base is an exciting way to score runs. With one out and any situation with a runner on base (including third base) the Diamondback’s .24 (and .23) hits per PA were 10% higher than any of the other situations.

Walks. With two outs and a runner on third base, the Diamondbacks’ .12 walks per PA were 20% higher than any other situation. The downside is that some of those walks were to get to the next batter and a better matchup for the pitcher.

Positive PAs and wOBA. With one out and any situation with a runner on base (including third base) these measure were about 10% higher than any of the other situations. Some explanations were less strikeouts, more balls-in-play, more hits, and some positive RE-24 when batters were out.

Perhaps there is room to improve batter performance with one out and runners on base. It is unclear why performance is less with one out instead of two outs.

Batter out with positive RE-24. When the batter was out, positive RE-24 was nearly exclusive to situations with one out and runners on third base. The positive RE-24 happened as follows:

• 26 times with runners on first and third
• 10 times with a lone runner on third
• 8 times with the bases loaded

How often did a runner on third base score (excluding non-RBI scoring events)?

Definition for this question: I assumed all RBIs with a runner on third base score that runner (although in theory there are exceptions). That definition excluded undeserved scoring events (i.e. fielding errors, double plays, triple plays). Most readers know RBIs can happen with hits, BBs, HBPs, and when the batter is out (except for double plays and triple plays). Batters are not credited with RBIs due to fielding errors.

The following table shows RBI events (which was different than total RBIs), with a breakout of the four situations with a runner on third base.

Data from Baseball Reference.

It’s remarkable that the Diamondback batters’ results were so much better with one out compared to zero outs. Although reasons were previously noted, the magnitude of the impact on scoring was very large.

And it’s noteworthy that with runners on base but not on third base, that results were better than with one or two outs compared to zero outs. Perhaps the reason was a laser focus on scoring the run before the third out happened.

When were home runs most important?

In 2022, the Diamondbacks hit 173 home runs. Let’s look at baserunners when those homers happened:

Data from Baseball Savant,

With runners on third base, a lower percentage of RBI events happened due to homers. For the Diamondbacks, there were many ways (besides home runs) to score runs when a runner was on third base.

During the last five seasons, what changes happened in scoring the runner on third base with two outs?

With two outs, the Diamondbacks’ success scoring a runner on third base ranged from 18.9% to 21.8%, and was consistently slightly less than the average in the Majors. Because the percentage fell in 2022, regression to the mean would indicate that the Diamondbacks percentage will increase next season. In addition I expect a higher number of PAs with a runner on third base due to a renewed emphasis on achieving a higher OBP. The following graph shows a close approximation of whether a runner on third base scored (hits plus BBs/HBPs if they resulted in a run).

Data from Baseball Savant.

During the last five seasons, what changes happened in scoring the runner on third base with less than two outs?

In 2017, with less than 2 outs the average success scoring a runner from third base was about 51% per this FanGraphs’ article. For the last four Diamondback seasons, except for 2021, their percentage was above that 51% average.

Diamondbacks. Data from Baseball Reference.

Summary.

With one out and runners on base, the Diamondbacks were at their best in hits per PA, positive PAs, and wOBA. When one of those runners was on third base (again with one out) their strikeout rate was lower and their BIP percentage was higher.

With one out, the Diamondbacks achieved their highest RBIs per PA for each of the four ways that a runner could be on third base (3B, 1B & 3B, 2B & 3B, and bases loaded). The differences were large.

With runners on third base, home runs accounted for a lower percentage of RBI events per PA. The Diamondbacks scored the runner in other ways.

With less than two outs and runner on third base, that runner scored more than the average in the Majors. With two outs and runner on third base, that runner scored less than the average in the Majors.

Next season runners on base will likely score more often due to a higher percentage of RBIs per PA and because more runners on base due to a renewed emphasis on achieving a higher OBP.