Yes, you read that correctly. That does in fact say "high school baseball game" and not "endurance performance art." The game began on Thursday, and Chukyo High mercifully claimed a 3-0 victory over rival Sotaku High on Sunday morning, after which there was presumably much celebration, many high fives, and some kind of enormous trophy.
Nope, what do you think this is, some kind of feel-good sports movie? In fact, there was just more baseball, because the marathon contest was only the semifinal of the National High School Rubber Baseball Tournament. By the way, it's called "rubber baseball" because of the ball's composition and not because of what the starting pitchers' arms must surely have felt like. Yes, both starters stayed in for the entirety of the game -- Chukyo's Taiga Matsui threw a total of 709 pitches and Sotoku's Jukiya Ishioka threw 689:
Chukyo did get their celebration after all, going on to beat Miura Gakuen 2-0 in the tournament's final. Matsui even made a relief appearance, throwing 77 more pitches and making you feel just a little bit worse when you complain about having to stay at work for 10 extra minutes.