Daisuke Matsuzaka was a star in Japan before he even finished high school. (Naoya Osato/Kyodo News/Associated Press)

The legend of Daisuke Matsuzaka — the Boston Red Sox flameout and architect of the mythic “gyro ball” — began with a 148-pitch shutout in the summer of 1998.

That performance came in the round of 16 of Japan’s national high school baseball tournament, called the summer Koshien. A day later, he threw 250 pitches in 17 innings in the quarterfinal. The next day, he started in left field but then pitched in relief as his team trailed 6-0; it scored seven runs in the last two innings to win. Then he threw a no-hitter to win the championship game.

Matsuzaka’s place in Japan’s baseball folklore was solidified. The summer Koshien gets the hype of the NCAA men’s basketball tournament plus the “aw” factor of the Little League World Series. For the month of August each year, the Hanshin Tigers, a top-tier professional team, give up their home field so 56 high schools can compete every day on national television for one of Japan’s most revered athletic prizes.

“Everyone who plays baseball has dreamed of playing at that stage,” said Yosuke Tsuji, associate professor of global business at Rikkyo University in Tokyo. “And for fans, baseball is a pastime, and everyone watches the games over summer break.”

But the tournament is beginning to draw the ire of player safety advocates for a single reason: There are no pitch count limits.

Matsuzaka threw more than 500 pitches in 1998. Eventual New York Yankees standout Masahiro Tanaka threw 742 pitches in 52 2/3 innings over six outings in 2006, and that wasn’t even the most pitches thrown in that tournament. That came from Yuki Saito, who threw 948 in 69 innings. He earned the nickname “Handkerchief Prince” after TV cameras spotted him wiping away sweat with a pale blue cloth during breaks in action.

At the 2018 tournament, Kosei Yoshida led Kanaashi Agricultural High School to the championship game behind 881 pitches over 50 innings in six outings, all in the span of two weeks.

Koshien stats: Kosei Yoshida, Kanaashi Agricultural High School

Date W L IP BF H R ER BB SO HP P#
Aug. 8 1 0 9 39 9 1 1 2 14 0 157
Aug. 14 1 0 9 36 6 3 3 2 13 1 154
Aug. 17 1 0 9 42 12 2 1 3 14 1 164
Aug. 18 1 0 9 36 7 2 1 0 10 0 140
Aug. 20 1 0 9 37 9 1 1 0 7 1 134
Aug. 22 0 1 5 32 12 12 11 3 4 0 132
Total 5 1 50 222 55 21 18 10 62 3 881

Those performances make Koshien so alluring, year after year, Tsuji said, but also are a lightning rod for criticism.

“People will watch it no matter what, but with a pitcher like Yoshida, they’ll start to learn his situation, about his high school, about the other players,” he said. “They’ll jump on the bandwagon like any other popular team.”

Smaller high schools such as Kanaashi don’t have deep enough talent pools to compete with larger powerhouses such as 2018 champion Osaka Toin, which also won the spring national championship. Although Toin has a clear ace, it also has a bullpen and other starting pitchers, too.

Kanaashi, which last made the tournament in 1915, does not. The way most teams have one shortstop or one center fielder, against top competition, Kanaashi only has one pitcher it turns to: Yoshida.

“It’s abusing these players, I think,” Tsuji said. “Adults have the responsibility to think about these pitchers and their health and make changes to the tournament. I do enjoy it, but I do think there need to be changes made. These pitchers are 16, 17, 18 years old. They’re too young to make these decisions. The adults have to do something.”

But that’s unlikely, said both Tsuji and Nick Watanabe, assistant professor of sport and entertainment management at the University of South Carolina. Koshien is a tournament steeped in national tradition that has largely gone unchanged since its inception. Winning the tournament as a coach is seen as a pathway to Japan’s college or professional ranks. Top players can become major league prospects or, at the least, will have major fan followings if they play Japanese college or pro ball.

And instituting a pitch-count limit similar to ones used in the United States — high school pitchers in most states can throw at most 120 pitches, but then require four days’ rest — would severely disadvantage public schools, especially rural ones such as Kanaashi, that cannot recruit players.

Imagine if Maryland Baltimore County played Virginia in the NCAA tournament, but UMBC had to use walk-ons and Virginia could use its full star power, Watanabe said. The Retrievers’ seemingly impossible upset would have been truly impractical.

But Koshien critics remain a minority of Japanese baseball fans, Tsuji said. Audiences still want to watch the same teenagers on the mound day after day, playing into the tournament’s century-long tradition of self-sacrifice and stunning underdog victories.

“You can tell me everything you want about Matsuzaka’s career. It will come down to me about what he did at Koshien, which is 17 innings of pitching,” said Watanabe, who grew up in Japan. “When you say Daisuke Matsuzaka, I can see him in that Yokohama uniform.”

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