Tatsuya Imai recently agreed to a contract with the Houston Astros. Before the contract agreement was announced, David Adler of MLB.com wrote an article about the pitcher, making five MLB comparisons for him.  Imai's fastball was among the comparisons, as Adler made the connection to Minnesota Twins ace Joe Ryan's heater.

"Ryan, like Imai, throws his fastball from a low slot (he had a 26-degree arm angle in 2025) with very similar induced rise (14 inches, the same as Imai) and run (13 inches to Imai's 15)," the article reads. "Imai's fastball has the potential to be like Ryan's, which would make it a very effective MLB-caliber heater. But there's also an X-factor for Imai in MLB: his velocity. Imai sat at 95 mph in NPB in 2025, but he showed the ability to dial up his four-seamer much higher than that."

Joe Ryan, Tatsuya Imai's Fastballs Receive Comparison

It goes without saying, but drawing a comparison to an established MLB pitcher who happens to be an All-Star is impressive. According to Baseball Savant, Ryan's fastball run value was in the 93rd percentile last season. The pitch plays a huge role in helping Ryan find overall success. It is not the fastest pitch in the league -- it sits in the 37th percentile for fastball velocity -- but Ryan's arm angle and ability to throw it for a strike makes it a challenging offering for hitters.

If Imai can throw even harder while locating the pitch, he could certainly end up having one of the better fastballs in the league. Ryan's heater is already a tremendous pitch, yet his velocity does not compare to other flame-throwers in the sport.

It will be intriguing to see how often Imai throws his fastball. In 2025, Ryan threw the pitch over 51 percent of the time. He throws a number of other pitches such as a sweeper and a sinker, but he did not throw a single one of his other offerings more than 13.1 percent of the time. 

Ryan's offspeed stuff provides a nice chance of pace, but his fastball is clearly his bread and butter. Will Imai also heavily rely on his fastball, or will he implement offspeed pitchers on a more consistent basis? Only time will tell, but his fastball unquestionably will have serious potential if it is indeed similar to Ryan's heater.

It will be a must-watch pitcher's duel if Ryan and Imai happen to pitch against one another when the Astros and Twins play this season.