Is Shohei Ohtani on Track to Achieve 50-50 Milestone? Timing of Feat Still Uncertain

There are a lot of great baseball storylines to keep tabs on this month. Aaron Judge is on yet another historic tear. Bobby Witt Jr. and the Royals are crashing the playoff party. The Brewers and Guardians are showing the league that you overlook the Central divisions at your own peril. But it all pales in comparison to Shohei Ohtani’s pursuit of 50 home runs and 50 stolen bases, at least for me. The 50-50 club doesn’t have any members. Ohtani is alone in the 44-44 club, the highest current rung he’s attained, and it doesn’t look like anyone else will be joining him anytime soon. Ohtani himself probably won’t repeat this; this is a career high in steals by a mile, and I don’t think it’s a coincidence that it’s happening in a season when he isn’t pitching. Next year, I think that he’ll rein himself in more, but right now, we’re seeing what it looks like when a fast player decides that they really do want to steal all the bases they can. Of course, it helps that he’s also one of the most powerful hitters in the game – both to aim for the 50-50 target and because opposing pitchers walk him quite often.

Will he make it? I’m not sure, but luckily I have a method that lets me estimate the odds. When Judge hit 62 homers two years ago, I built a little tool to estimate the likelihood of him hitting that milestone, as well as the chances of it happening in any particular game. That method works pretty well in general, so I redid it with a few modifications to handle the fact that we’re looking at two counting statistics instead of just one. I’ll start by reviewing the methodology, though if you’re not into that, there are some tables down below that will give you an idea of when and where Ohtani might hit (or run into) this momentous milestone.

I started with our Depth Charts projection for Ohtani’s home run rate the rest of the way. That’s based on neutral opposition, so I also took opposing pitching staffs into account, as well as park factors for lefty home run rate. Lefties hit more homers in Dodger Stadium (12 remaining games) than in Truist Park (three remaining games), and batters hit more homers against the Rockies (six remaining games) than the Padres (three remaining games). I used park factor and opposition strength to modify Ohtani’s baseline home run rate and create a unique home run rate for each remaining game. I then picked a random number of plate appearances (four, five, or six, with five the most frequent) for each game. The Dodgers will likely give Ohtani at least one day off the rest of the season, so I built that into my calculations. I don’t know which day it will be specifically, so I had my simulation pick a random day in Los Angeles’ upcoming 10-games-in-10-days stretch. I also made a slight adjustment to better reflect reality: Instead of having a static home run rate, Ohtani’s true home run talent fluctuates randomly around his projected rate, which means that sometimes he hits home runs 8% of the time in this simulation, while sometimes it’s closer to 5%. Projecting the chances of him hitting 50 homers is pretty easy that way. The distribution of possible games he’ll do it in looks like this:

That’s not the question we’re asking, though. Fifty homers is cool but hardly unheard of. We’re hunting for 50-50 seasons. To do that, I added a second counter for stolen bases. I didn’t use park and team factors here, I just took a projected steal rate for Ohtani and applied it to the remaining games. I did make one modification, though. Obviously Ohtani can’t steal a base if he hits a homer, so I subtracted each game’s homer total from its plate appearance total for the sake of modeling stolen bases. In other words, if he batted five times and hit two homers, I’d only simulate a chance of a steal in the remaining three PAs. From there, things are pretty easy. When sim-Ohtani hits his 50th homer, the simulation checks to see if he already has 50 steals. If he does, that game is his 50-50 day. If he doesn’t, then the simulation for stolen bases for that day runs. On the day of his 50th steal, the same thing happens in reverse – if he already has 50 homers, then that’s the day he hits 50-50. If not, the simulation keeps going. In this way, we can get the joint odds of the two things happening instead of the independent odds of each one.

The sum probability of Ohtani hitting both totals is around 56%. That makes intuitive sense to me – we’re projecting him for 50 homers and 51 steals, and I think the remaining parks and opponents bias the home run total upward. The joint probability can’t be much more than 50%, but I don’t think it should be much less either, given that he’s pretty likely to hit the steals total. I peg those odds at around 84%. That’s higher than you’d expect from our projections, but a lot of stolen base rate comes down to intent, and I’m fairly sure that Ohtani intends to steal 50 bases this year, so his go rate is likely higher than our naive projections. The distribution of days where Ohtani might go 50-50 looks like this:

In other words, if you can only go to one game and want the best chance of seeing a record-setting event, you should go to the first game of the final series of the year in Colorado. If you only want to go to one series, it should be that one. Ohtani could certainly hit both totals earlier, but it’s difficult given that doing more of one event implies less of the other. That’s not to say there’s no chance of an early milestone. There’s a roughly 7% chance that Ohtani hits both plateaus before the final homestand of the year begins on September 20, and a further 30% chance of him hitting it during those six home games. If I were hunting for a specific time to go see him, I’d pick that one: at home, against first a bad pitching staff and then a division rival. One thing worth noting is that these odds can change fast. If Ohtani hits a homer and steals a base tomorrow night, the odds shoot up into the mid-70s immediately. The most likely time to see the 50-50 game moves up to the…