An Early Perspective.
Inspiration.
On 13 April, in the postgame interview Torey Lovullo said how many baserunners the Diamondbacks had in that game. Likely his words reflected that the number of baserunners is important. His words thrilled me because every game I have tracked what happened to the baserunners. It is important!
Background.
Three outcomes happen to baserunners. They are called out on the basepaths, they cross home plate to score, or they are left-on-base (LOB) at the end of innings.
Last season, things that led the Diamondbacks to scoring the most runs in the Majors were:
- 1811 baserunners (two sigma more than the 21-23 average).
- High percentage (7.7%) of baserunners scored because of home runs (these runs exclude the batter).
- High percentage (27.3%) of baserunners scored because of non-homers.
For more details see this AZ Snake Pit article.
The 2025 Season.
The table (which follows after some points are made) shows:
- The percentage of baserunners scored by non-homer remained at last season’s excellent level, before and after Ketel Marte was injured.
- The overall percentage of baserunners scored by home runs remained at last season’s excellent level for the first 16 games. However, it fell from better than excellent before the Marte injury to about 42% of excellent after the injury. But Marte’s absence did not appear to impact that statistic because he hit zero home runs this season. Looking at when the Diamondbacks hit home runs, two batters hit a total of 7 home runs before Marte’s injury and zero after Marte’s injury: Eugenio Suarez and Lourdes Gurriel Jr.. It appears the impact on the statistic was from those two batters having a cold streak.
- The number of baserunners per game fell from 11.9 per game to 10.3 per game after the injury. The Diamondbacks need to increase baserunners per game up to last season’s level (11.2).
Diamondbacks, 2025 Season. Data from Baseball Reference.
The three statistics (BR/game, % BR scored via homer, and % BR scored via non-homer) were worse after Ketel Marte’s injury. Although the table does not show reasons, I’m confident that absence of Ketel Marte made a negative impact. I’m looking forward to Ketel Marte’s return.
Additional Depth of Analysis.
This season, the Diamondbacks’ baserunners took extra bases at a much higher rate (55%) than the league average (43% through 13 April). Those extra bases taken contributed to a high percentage of baserunners who score. Data from Baseball Reference.
This season, let’s split the Diamondbacks batting into batting with baserunners, and batting without baserunners. Let’s look at positive results by the batter (singles, doubles, triples, home runs, walks, and hit-by-pitch). The comparison is in the following table.
Diamondbacks. Positive PAs are singles, doubles, triples, homers, walks, and hit-by-pitch. Data from Baseball Savant.
In the first 16 games this season, with no baserunners the Diamondbacks had a 5% better percentage of positive outcomes than last season.
Before the Marte injury, with runner(s) on base the positive outcomes were about the same percentage as last season (when the Diamondbacks had the highest percentage in the league). After the Marte injury the positive outcomes fell to 27.8% (which was below league average).
Summary.
Last season, the Diamondbacks scored the most runs in the Majors. A big reason was their high percentage of baserunners who scored.
For the first 16 games of this season, the overall percentages of Diamondbacks’ baserunners who scored was as good as last season, for both homers and non-homers (see Table 1).
When Ketel Marte was injured, things changed (see Tables 1 and 2).
- Before the Marte injury, with runner(s) on base the positive PA outcomes were about the same percentage as last season (when the Diamondbacks had the highest percentage in the league).
- After the Marte injury the positive outcomes fell to 27.8% (which was below league average).
- After Ketel Marte’s injury the percentage of baserunners who scored because of home runs fell by more than half. Perhaps the reason was less homers by Eugenio Suarez and Lourdes Gurriel Jr..
The Diamondbacks took extra bases more often than the league average (55% vs 43%), contributing to a higher percentage of baserunners scored.
In the first 16 games this season, with no baserunners the Diamondbacks had a 5% better percentage of positive outcomes than last season (see Table 2).