Here’s Why Michael Busch Isn’t Starting Against Lefties

Michael Busch boasts a .267/.363/.510 slash line with 11 homers and a 146 wRC+ that puts him eighth among all first basemen when it comes to creating runs. Yet he’ll sit in back-to-back games and has only gotten 34 plate appearances against left-handed pitchers while Justin Turner picks up semi-regular starts despite a 67 wRC+ that is less than half that of his younger counterpart.

When we just look at the box score numbers, the math doesn’t make much sense.

If we take a quick look at the splits, however, Craig Counsell‘s strategy becomes transparent. In his (limited) action against lefties, Busch is slashing .138/.265/.172 with a 37 wRC+ and no homers. Turner has gotten 54 PAs against lefties, over which he’s slashing .265/.315/.347 with an 89 wRC+ and one homer. Over the last 34 of those PAs, Turner is at .294/.294/.412 with a 98 wRC+ and a double to go with the dinger. Are those tremendous numbers? Hardly, but they’re still a massive step up from what Busch has done.

On one hand, I can see the argument for giving more at-bats to the superior overall player. On the other, and this is far more important, the manager’s job is to maximize matchup leverage points on a game-by-game basis. While Busch is clearly the better hitter and first baseman over a broad sample, Turner is better in certain situations. And as a right-handed hitter, those situations come with southpaws on the mound.

The strongest counter to this argument is that Busch had a .712 OPS with a 103 wRC+ over 89 PAs against lefties last season. But with Patrick Wisdom as the only right-handed alternative at first — apologies to Garrett Cooper‘s brief tenure — Counsell didn’t have a viable option for short-side platoon help. Wisdom had a very rough 2024 on the whole, and posting a 41 wRC+ against lefties while playing first didn’t help.

This is less about what Busch can or can’t do and more about what Turner has done and is doing. It’s certainly not unreasonable to imagine the 40-year-old’s performance eroding over the next few weeks or months, at which point Busch can be given a little more run in those like-handed matchups. Until then, maintaining this little timeshare makes the most sense for the team’s performance.