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Nick Senzel and Josh VanMeter are 24-year-old rookies with the Reds. They were roommates when playing for the AAA-Louisville Bats and refer to themselves as “best baseball friends.” Reds manager David Bell has used Senzel to lead off against left-handed starting pitchers and, in the absence of Jesse Winker, writen VanMeter’s name in at the top of his lineup card when the Reds face a right-handed starter.
Bell’s reasoning is clear after taking a look at the split performances of his rookies. Senzel has hit left-handed pitchers well, while struggling against right handers. VanMeter’s production has been the opposite, although he’s only been given 19 plate appearances against LHP compared to 157 versus RHP. Let’s take a look at the basic numbers.
First, the two rookies against right-handed pitchers:
VanMeter has a clear edge over Senzel in all categories. He walks more and strikes out less. His batting average is 50 points higher. The walk differential makes the OBP gap 70 points. VanMeter has an edge in power with a .187 ISO compared to Senzel’s .157 ISO. (Isolated Power – ISO – is the difference between slugging percentage and batting average. It’s a pure measure of extra-base hitting.)
Overall, against right-handed pitchers, Senzel has produced runs at 18% less than league average while VanMeter has produced at an impressive 22% above. The large gap between the two hitters persists when luck and defense are neutralized in xwOBA.
When we look at Senzel and VanMeter against lefties, we see the opposite relationship:
Senzel has 90 plate appearances against lefties while VanMeter has just 19. VanMeter’s stats here are hardly worth publishing since the sample size is so small. But with Nick Senzel, we see he has been well above average (29%) against lefties.
Nick Senzel and Josh VanMeter aren’t playing the same position for the Reds, so this isn’t a standard platoon situation. Instead, the two rookies are taking turns batting leadoff depending on the opposing starter. Senzel plays against RHP but bats toward the bottom of the lineup. VanMeter usually doesn’t play against LHP as Bell takes that opportunity to play Phillip Ervin.
Based on the numbers, it’s easy to see why Bell is doing what he is with the lineup.
