Kodai Senga’s Rookie Year as NYM’s Ace

Mets have 0 regrets signing Japan’s forkball ace

Going into the 2023 season, the Mets had Scherzer and Verlander as expected 1-2 pitchers. Quickly the train went off the rails and both pitchers were hurt and performing poorly, only to be traded away mid-season.

The spotlight turned to Senga, who pitched his way to a ROY runner-up with 29 starts, a 2.98 ERA, and a 4.5 WAR.

Pitch counts

Senga throws 3 main pitches: Fastball, Cutter, Forkball.

pitch typeRelease speedpercentage thrown
Kodai Senga’s pitching arsenal is highlighted by MLB’s rarest pitch type – the forkball. The forkball is a variant of the splitter known for its big downward break as it approaches the plate.

As far as his fastball and cutter goes, Senga throws decent speed but nothing out of the ordinary. His forkball is his specialty and is used heavily in getting batters out.

Pitch count with n strikes

pitch type (o strikes)percentage thrown
Senga starts the at bat with fastball as the main pitch. He will very rarely throw the forkball.

pitch type (1 strikes)percentage thrown
With 1 strike he is still fastball-cutter focused, but will throw the forkball ~25% of the time.

pitch type (2 strikes)percentage thrown
With 2 strikes, Senga is taking full advantage of his forkball – throwing it close to 50% of the time!

The strikeout pitch

Senga had 202 strikeouts in 2023. 55% of them came from the Forkball, 30% came from Fastball.

Visualizing pitch data

Let’s visualize where Senga pitches at specific pitch counts.

Data Source

We used R to get this data and report!

baseballr, calledstrike