'Baseball is baseball': Famed Japanese slugger Sasaki ready for pro journey

Rintaro Sasaki stepped off a plane onto U.S. soil for the first time in September 2023. The then-18-year-old -- Japan’s all-time high school home run leader -- had never left his home country, didn’t speak English and was about to embark on a one-of-a-kind journey in pursuit of his Major League dream.

So, naturally, he got in the car and went straight to Oracle Park in San Francisco to take in a big league game.

It’s hard to convey just how big of a star Sasaki is in his native Japan. He reached celebrity status as a teenager for his prodigious power exploits and nearly everything he does on the field has become a social media sensation -- his more than 86,000 followers on Instagram are more than the two top 2026 Draft prospects Grady Emerson (No. 1) and Roch Cholowsky (No. 2) combined. He was the subject of the MLB Pipeline Instagram post that received the highest number of total impressions (1.77 million) in 2024, outperforming Paul Skenes, Jackson Holliday and other famed prospects from that year.

Even during the MLB Draft Combine in June, more than half a dozen Japanese media members flocked to speak with him after his impressive batting practice showcase that featured a titanic 458-foot homer and some of the highest exit velocities (max 115.4 mph) at the event.

Further enhancing Sasaki's public profile is how directly intertwined he is with four-time MVP Shohei Ohtani, whose own fame in Japan is ubiquitous and unrivaled.

Sasaki played for Ohtani’s father, Toru, during his “Little Senior” days, the next step up from traditional Little League before players enter the competitive high school ranks. Conversely, Ohtani played for Sasaki’s father, Hiroshi, at Hanamaki Higashi High School in Iwate, Japan, which also produced eight-year big league veteran Yusei Kikuchi.

Having first met Ohtani and Kikuchi as a child, Sasaki has since closely followed their careers and cites them both as an inspiration for his Major League dreams.

“I took a picture with them, I still have it,” said Sasaki, who has gotten so comfortable in English that he did all of his pre-Draft interviews in the language. “That’s a good memory. That’s why they’re my favorite players in my whole life -- they’re great guys. We have a good relationship.”

Sasaki’s goal has always been to find a way to the Major Leagues. Despite being the projected No. 1 selection in the 2024 NPB Draft, the slugging first baseman announced that he would instead attend Stanford, one of college baseball’s premier programs that is also world-renowned for its academic excellence. Draft-eligible as a sophomore this year, it gave him a much more direct path to a big league organization than waiting nine years to become an international free agent or having a club in Japan post him for MLB clubs.

Before Sasaki ever stepped foot on campus for the Cardinal, he took part in two of MLB’s premier developmental circuits -- the MLB Draft League and Appy League over the course of the summer. After slugging 140 homers during his high school career, Sasaki naturally crushed a roundtripper in his first game stateside for the Trenton Thunder on June 11, 2024.

After a solid, albeit unspectacular, freshman campaign for Stanford (seven homers, .790 OPS), Sasaki found his rhythm this spring with 16 roundtrippers and 47 RBIs in 54 games, walking nearly as much as he struck out en route to a .952 OPS.

The acclimation aspect of baseball in Japan vs. the United States wasn’t as difficult as the cultural one. “Baseball is baseball,” Sasaki said, and while he was used to being away from his family after living in a dorm during his high school days, he’s had to deal with the rigorous academic aspect mixed in with learning both a new culture and foreign language.

“Physical fatigue is one thing, but controlling your emotions and your thoughts is harder,” Sasaki said before the start of the 2026 season. “Even when you’re doing something you love, it’s not always easy to maintain the same level of motivation every single day.”

Still, he remains a bit of an enigmatic presence as a prospect -- he’s likely limited to first base in the pro ranks and stole just one bag across 106 contests in college. He produces top-of-the-charts exit velocities and home run distances, but how often he gets to that power will be the separator of whether he finds consistent success in the pro game.

Sasaki will also have a choice to make. Both the Yokohama DeNA BayStars and Fukuoka SoftBank Hawks selected the slugger with their first-round pick last October, before Fukuoka won exclusive negotiating rights should Sasaki choose to return to Japan and play in NPB.

Regardless of the next step that Sasaki chooses, it’s clear that he has opened doors for other Japanese players who are looking to test their mettle in the United States: Right-handed pitcher Genei Sato was also set to be a potential first-round pick in the NPB Draft, before declaring his intention to attend Penn State before becoming MLB Draft-eligible as early as 2027. In January 2025, two-way player Shotaro Morii received the highest bonus ($1.51 million) of any amateur Japanese player in history when he joined the Athletics organization, bypassing the college route in both countries to get his pro career underway.

“I feel like I found a great way for Japanese guys from high school, how we’re going to step up to a high level,” said Sasaki. “People coming to U.S. college, going to pro baseball -- I think it’s great.”