The best season ever? How Shohei Ohtani's 2021 compares to the greats

Photo by John Cordes/Icon Sportswire

The most remarkable aspect of Shohei Ohtani's season isn't just that he's doing it -- the top slugger in the game, one of the best pitchers -- but that he was allowed to attempt it in the first place. Baseball historian Bill James made a point about this recently, writing, "Over time, any closed structure tends to exclude ideas, exclude innovations, exclude minority approaches to a problem. ... It is usually players from outside the system who break through the shibboleths, and demonstrate that these things CAN be done."

True. Except ... two-way players aren't a thing in Japan, either. Ohtani not only challenged the conventional thinking in the majors, he challenged the conventional thinking in Japan: In professional baseball, you're either a position player or a pitcher. Ohtani wanted to do both.

He leads the majors with 41 home runs and is a candidate to lead in other categories -- OPS, slugging percentage, total bases, extra-base hits. As a pitcher, he is sixth in the American League in Baseball-Reference WAR. Among all major leaguers with at least 100 innings, he is seventh in lowest batting average allowed, 11th in strikeout rate and 12th in OPS allowed. Oh, to top it off, he's in the top 10 in the majors in stolen bases.

It feels like it should be impossible to be one of the best hitters in the game and one of the best pitchers. Even Babe Ruth, when he played both ways in 1918 and 1919 against a much different level of competition, didn't dominate like this on both sides of the ball:

Ohtani, 2021: 159 OPS+, 153 ERA+
Ruth, 1918: 192 OPS+, 122 ERA+
Ruth, 1919: 217 OPS+, 102 ERA+

It is a transcendent season, but is Ohtani having the greatest individual season ever? You could answer that in two ways:

1. Just look at estimated value, whether it's WAR or James' win shares system.
2. Consider the iconic status of the season, basically, "Will it be remembered?"

With baseball being a numbers game, we tend to focus on value, but it seems the greatest seasons should be some combination of the two.

Ohtani will fall short in pure value. His Baseball-Reference WAR is 7.8, giving him an outside chance of a 10-WAR season, although he'll need a big September to get there. There have been only four 10-WAR seasons over the past decade -- two by Mike Trout, one by Mookie Betts and one by Aaron Nola -- so that's rare territory, but well behind the all-time leaders. Ohtani is at 32 win shares, so he has a good chance at reaching 40. There have been just four of those seasons in the past decade -- three by Trout and one by Andrew McCutchen. Again, rare territory, but the all-time great seasons reach 50 win shares.

Ohtani's season will certainly be iconic, doing something nobody has done since Ruth (or Bullet Joe Rogan in the Negro Leagues). Is it the greatest season ever? Let's take a trip through MLB history and pick the greatest season of the decade since the 1900s. Then you can decide.