Fresh off a successful 25-game stint in the MLB Draft League, Japan's all-time high school home run leader Rintaro Sasaki moved his stateside debut to the Appalachian League on Thursday. Follow along as he suits up for the Greeneville Flyboys.

Just 19 years old, Sasaki has already established a reputation as a prolific slugger and will enroll at Stanford University in the fall, which means he'll first be MLB Draft-eligible come 2026. He made his overall stateside debut in June in the Draft League with the Trenton Thunder.

Sasaki made an immediate impression, homering as part of a three-RBI performance in his debut and hitting .221/.387/.395 with four homers, 17 RBIs and nearly as many walks as strikeouts across 25 games for the Thunder. His next stop is the Appalachian League, a 10-team summer collegiate baseball league that is part of the Major League Baseball and USA Baseball Prospect Development Pipeline.

Sasaki's move to the United States was a largely unprecedented one that enables the teen phenom to subvert the posting system that Japanese players are traditionally subject to when making the move from pro ball in their native country. When it comes time, he will also be eligible to appear on MLB Pipeline's top Draft -- and if he signs -- and prospects list as well.

He has a direct connection to the Major League game in the form of Blue Jays left-hander Yusei Kikuchi, who used to babysit Sasaki during his childhood. Sasaki's father was Kikuchi's high school coach.

The Appalachian League's regular-season schedule runs through July 31.

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