STANFORD, Calif. — The dugout chatter for intrasquad games at the Sunken Diamond can be merciless.

The slings and arrows are nonstop when Stanford baseball players are pitted against one another. The guys wearing red jerseys shout streams of insults at players on the black team and vice versa. “Whoa, hey, Luke’s got a new stance,” a player wearing a black jersey yells as freshman catcher Luke Lavin stands upright in the batter’s box, perhaps imitating the Chicago Cubs’ Cody Bellinger.

Lavin pops up the next pitch. “Same swing, though!”

But the tone changes when No. 3 for the black team, a husky teenager and early enrollee who won’t begin his freshman season until next year, steps in the box. The good-natured ribbing gives way to full-throated encouragement from both sides. Let’s go Rintaro! C’mon Rintaro! Give it a ride, Rintaro!

“We still can’t believe he’s here,” infielder Jimmy Nati said. “We’re all fanboying him, for sure.”

Rintaro Sasaki is not the typical Stanford baseball recruit. Back home in Japan, he is a national celebrity, instantly recognizable almost anywhere he goes. Last year, Sasaki was the top-rated high school player in a country where high school baseball is a national obsession. The left-handed slugger was projected to be the most coveted name in last October’s Nippon Professional Baseball draft. He mashed a national record 140 home runs, with twice as many walks as strikeouts, for Hanamaki-Higashi High School in Iwate Prefecture, the same school that produced Los Angeles Dodgers superstar Shohei Ohtani and Toronto Blue Jays left-hander Yusei Kikuchi. Sasaki’s father, Hiroshi, coached all of them and is a legendary figure in his own right.

When Rintaro graduated from high school this past March, television stations dispatched more than 30 camera crews to cover the event.

It would be a last glimpse. Sasaki announced a few weeks prior to the NPB draft that he would not register for it. Instead, he would blaze a trail and play collegiate ball in the United States — a nearly unprecedented path that could fast-track him to Major League Baseball as a draft-eligible sophomore in 2026.

In February, Sasaki stunned Stanford coach David Esquer and recruiting coordinator Thomas Eager when he requested a Zoom call with them, asked a few logistical questions, then told them that he was selecting the Cardinal over Cal, UCLA, and Vanderbilt.

Sasaki arrived on campus at the beginning of April, moved into a dorm room and enrolled in three classes as a pre-freshman. He can participate in all team activities except playing in games. He practices and works out with his new teammates. On game days, he suits up, cheers them on from the dugout and eagerly takes part in all the pregame traditions. He’s gone on road trips to Utah and Oregon State. He’s surprised everyone with how much English he understands, and he’s left them slack-jawed with his batting-practice shots over the light standards. When he turned 19 on April 18, his teammates took him out to a dinner that included ice cream, candles and tables of complete strangers joining in to sing “Happy Birthday.”

He is absolutely loving all of it.

“I made the right choice,” Sasaki said through interpreter and team trainer Tomoo Yamada. “People are nice to me. Everyone is my friend. I haven’t missed Japan yet. I feel completely settled. I can’t believe it’s been only four weeks. I’m enjoying life.”

Beyond the right field fence at Klein Field, past the scoreboard and a stand of trees, is the Avery Aquatic Center. It’s where Olympic swimmer Katie Ledecky would lap the competition during her brief time as a Stanford student. As best as anyone can tell, that’s where a couple of Sasaki’s tape-measure home runs have splashed down.

Everything about Sasaki is broad and powerful, a body rendered in letterbox format. He stands 6 feet and 250 pounds, and his full-tilt swing puts every ounce behind the baseball. He hits line drives to left field that dismiss gravity as they streak over the fence. His pull power is pure astonishment. The ear-splitting sound off his aluminum bat exceeds OSHA safety standards.

“He looks like Barry Bonds,” Nati said. “That’s how good he’s going to be. When he runs into balls, he hits them over the light tower. It’s crazy.

“The ball comes off different. You can close your eyes, hear the sound and know it’s him.”

In a simulated game at Stanford last Wednesday, Sasaki lined a single off the fence and crushed two homers. According to Trackman, the second homer traveled 422 feet, with an exit velocity of 111 mph.

“Hey Rintaro,” Esquer called out. “You’ll need to get that one out of the swimming pool.”

“Swimming pool?” Sasaki replied, then nodded and laughed. He knew what the words meant. He just needed a second to process them.

Here’s another word to add to his growing vocabulary: Trailblazer.

“Ah, pioneer?” Sasaki said in English. “Yes, I know it.”

If Sasaki had been drafted by an NPB team, he would have been under club control for nine years. Although Japanese pro teams often gain a windfall in posting fees by making their players available to MLB before their nine years are up, there are no guarantees. Sasaki might have been pushing 30 by the time he had an opportunity to play in the U.S.

He made it clear: His goal is to play in the major leagues.

“Ohtani and Kikuchi are already overseas,” Sasaki said. “I always thought one day, hopefully I can get there. They were big influences for me. Ohtani said, ‘Follow your instinct. That is what you decided. That is a path you need to keep walking.’”

Sasaki’s path — to become MLB draft-eligible by attending an American university — has almost no precedent. Rikuu Nishida, a speedy infielder from Sendai, was an 11th-round pick of the Chicago White Sox last year after a standout season at the University of Oregon. But Nishida, who played two seasons at a junior college upon arriving in the U.S., was not an NPB draft prospect in Japan.

Although there are no written rules that would prohibit an MLB team from signing a Japanese high school player out of its international signing pool, there’s been an unofficial understanding among teams against the practice. (Until 2020, when it rescinded its rule, NPB enforced a ban of two to three years on Japanese players who opted out of the draft and signed with a foreign league.)

Ohtani came close to setting a groundbreaking precedent as a high school phenom in 2012, when he advised NBP teams against drafting him, saying that he intended to sign with an MLB franchise. The Nippon Ham Fighters took him anyway, then persuaded him to sign by promising to let him develop as a two-way player.

NPB teams had no such hope of signing Sasaki, who ensured that he would be taken off the NPB draft board by attending an American university. Now he will have two seasons to improve his conditioning and address weaknesses in his game before turning pro.

The chance to develop in less of a fishbowl environment was appealing to Sasaki and his father, as well.

“In Japan, people tend to focus more on shortcomings. But in the U.S., they develop individuality,” Hiroshi Sasaki told CNN in March.  “I think this is a very good choice for him.”

It is a choice that involves financial risk and delayed gratification. As a first-round pick in NPB, Sasaki likely would have received a signing bonus and incentives worth more than $1 million, plus personal services contracts that could have earned him hundreds of thousands more. At Stanford, of course, he is merely a student-athlete on scholarship. He also cannot participate in NIL opportunities while on U.S. soil because he is an international player on a student visa.

He would earn a multimillion bonus if he is a first-round pick in 2026, but that is far from assured. Because he is limited to first base and his defensive skills are unpolished, his bat must be compelling. And although he faced top high school competition in Japan, advancing to the Best Eight at the famed Koshien tournament last year, he mostly hit against pitchers who threw in the upper 80s.

He is betting on himself. And on Stanford to help him develop his gifts.

“I had the confidence to come to the States,” Sasaki said. “Right now I want to settle in here, take classes and do well. Take one step at a time. And two years from today, we’ll see where I am at. Getting to the major leagues is not everything for my life. Of course I want to get drafted and get to the major leagues. But I want to keep studying and also be a good person.”

Does that make him a pioneer? He shrugged. That’s for others to decide.

“He’s showing a lot of courage to come here spring quarter, practice on a daily basis with a college team and look so comfortable,” Esquer said. “He wants to get an education and maybe become an entrepreneur, but he’s also told us that he wants to leave a mark and blaze a trail for Japanese players to come here and play college baseball. Eighteen-year-old kids don’t normally think that way.

“He grew up with Ohtani. He’s seen the standard of what it takes to be great.”

If Sasaki becomes a top MLB draft prospect two years from now, he’s likely to be regarded as the baseball player who upended an entire system — something that even Ohtani could not accomplish.

Ohtani, asked about his influence on Sasaki’s decision, said he merely offered support and encouragement.

“I didn’t really offer any advice or anything like that,” Ohtani said through Dodgers interpreter Will Ireton. “Making the best decision usually comes from being convicted. I’ve made decisions like that in the past as well. I feel like that’s the decision he made from his conviction.”

Sasaki (right) has known Ohtani since he was young, and has turned to the megastar for advice over the years. (Courtesy of the Sasaki family)

Esquer and his coaches still have trouble believing Sasaki is here.

Stanford was a late entrant when the recruitment process began last year. Sasaki took unofficial visits to Vanderbilt, Duke, UCLA and Cal — he also attended a Giants game at Oracle Park — but did not go to Palo Alto. At the time, there wasn’t a spot for him at Stanford, which allows a strict number of admissions per sport. Then two Cardinal players entered the transfer portal and a few others de-committed.

Suddenly, Stanford had a spot — and plenty of interest.

“We were playing catch-up, to be honest with you,” said Eager, who is the team’s pitching coach as well as recruiting coordinator. “In the Japanese culture, because we weren’t involved in the first go-around, we didn’t know if they would take it as a sign of disrespect. We hoped to explain that this is just how it operates here. We liked him all along. And we had a good official visit in January. But I tell you what, I did not think we were getting him.”

The official visit included meet-and-greets with three Stanford alums who are major leaguers: Chicago Cubs second baseman Nico Hoerner, Kansas City Royals pitcher Kris Bubic and San Francisco Giants pitcher Tristan Beck. Hoerner drew on his experience playing with Japanese outfielder Seiya Suzuki in Chicago while encouraging Sasaki to make sure he could continue the routines that are important to him.

“You can do your best to put yourself in someone’s shoes, but it is a totally different experience what he’s going to be doing,” Hoerner said. “The adjustment to college, even for myself, driving 45 minutes from where I grew up, was really different. Doing that with a language barrier, taking classes, and the whole schedule is a lot.

“In pro ball, you’re in charge of your own career at the end of the day. But a lot of times in college, you’re pretty much subject to whatever the program believes in. So I just felt it was really important to stress that whatever it is that makes him tick as a player, he’d be able to continue to do that. Because not all college programs would really be (OK) with that. And I did feel like Stanford, with the staff that they have, are there for whatever the players need.”

Esquer knew what was at stake, even beyond adding a potential impact hitter. If Sasaki chose Stanford, it would enhance the university’s already prestigious international brand. And if Sasaki became the first arrival that breaks a dam, perhaps the pipeline of talent from Japan would lead directly to the Sunken Diamond.

Sasaki’s visit was thorough but not ostentatious. The team hired a taco truck to cater a post-practice party. Several players remarked that they saw Esquer wearing a suit for the first time. Mostly, Esquer hoped to convey that Sasaki would have every resource to develop as a player and person.

“My promise to you is that we’re going to take care of your son,” Esquer told Hiroshi Sasaki. “We’re going to coach him and help him get better, but also we’re going to make sure he’s well looked after.”

Beck laughed when he recalled his recruiting visit more than a decade ago. No taco trucks, no meetings with trustees, no coaches in suits. But he remembered one thing someone told him that might have resonated with an international celebrity like Sasaki.

“One of the adages I heard before I enrolled was, ‘Don’t worry about being bothered, because the most famous people here don’t play sports at all,’” Beck said. “The most interesting people here aren’t even athletes, even with people like Andrew Luck walking around campus.

“He did mention his favorite team was the Giants, which is sweet. I made sure he said that a couple more times so Nico and Kris were sure to hear it.”

Sasaki was projected to be a top pick in the NBP draft after hitting a national record 140 home runs in high school. (Courtesy of Stanford Athletics)

You might assume that Sasaki wants to become the next Ohtani. But there’s another home run hitter that he has spent his life emulating.

“I don’t know how far I can go, but I respect Barry Bonds a lot,” Sasaki said. “(To) one day get to be as close as possible to Barry Bonds — that is my goal.”

Bonds, and not Shohei?

“Ever since I was in elementary school, I was watching Barry Bonds,” Sasaki said. “Ohtani was one of my mentors. Sometimes I communicate with him and get advice. But Barry Bonds was my ultimate goal since I was little. Don’t misunderstand. I respect Shohei and Barry Bonds both.

“When Bonds got in the batter’s box, people expected to see something big or something special. I want to be like that.”

Rintaro Sasaki, my goodness.

Wish we could’ve seen this swing in NPB but I’m confident he’s going to blossom into a superstar. pic.twitter.com/ifkODlbc2g

— Yakyu Cosmopolitan (@yakyucosmo) April 30, 2024

For now, Sasaki just wants to be a good teammate and fit in. He is taking a language skills class with other international students, but his other two courses, including an introductory class in human biology, are in English. He understands more than he can speak, but baseball tends to operate with its own universal language. When Yamada, the trainer, returned to Japan for a week, Sasaki appeared to manage just fine. If Sasaki gets stuck on a word, bullpen catcher Michael Fung, who is minoring in East Asian Studies and spent time last year studying in Stanford’s overseas program in Kyoto, is usually able to help bridge any language gap.

Sasaki declined Esquer’s offer of a full-time interpreter, saying he would chip away at the language barrier faster with the help of his teammates.

“It fired us up to hear that,” said Lavin, who has become one of Sasaki’s more steady companions. “Because it seems he’s really bought into the team’s culture and being around us. He’s a normal teammate here. You can’t tell from talking to him that he’s super famous. He has not brought it up once, how many people know his name.”

Still, Sasaki is likely to draw crowds very soon. The word is just beginning to trickle out that he is on campus. At a recent game at Santa Clara University, two dozen Japanese baseball fans waited outside the ballpark so they could meet Sasaki and take pictures with him. Stanford officials are gearing up for more attention, more media and more fans.

For now, his competition is limited to those spirited intrasquad games. A couple of his teammates already feel comfortable enough to engage in a bit of sarcastic banter. And they’ve learned that Sasaki is already comfortable enough to dish it right back.

“We were at Oregon State and I’m watching him flick home runs the other way,” Lavin said. “So I said to him, ‘Ah, it’s just the wind.’ Then the wind died down and he started hitting pull-side homers over the stands.

“And he looked at me and said, ‘It’s not the wind.’”

The Athletic’s Fabian Ardaya and Patrick Mooney contributed to this story. 

(Top image: Sean Reilly / The Athletic; Photos: Courtesy of Stanford Athletics)