Kō Kitamura, whose family owns a sporting goods store, has known the Tsukishima girls since he was born. The Tsukishima family runs a batting center and cafe, and they have four daughters. There's Ichiyo, the responsible eldest; Wakaba, Kō's cheerful best friend; Aoba, who doesn't get along with Kō; and Momiji, the energetic youngest daughter. When Kō enters high school, he aspires to lead his baseball team to the Koshien National High School Championship as their ace pitcher and make Wakaba's dream come true.
Episodes
On one summer day, Wakaba leaves for camp after making a promise to Ko. A few days later, Ko happens to turn on the television, and a high school baseball game is on. During the exchange, a news report comes on, and Ko can't believe what he hears.
Wakaba asks Aoba what kind of boys she likes, Aoba says, "One who can throw a 100 mph fastball." Wakaba says that Ko may one day be able to throw that fast. Ko and Nakanishi's team faces Aoba's pitching in a sandlot baseball game. Aoba wins, but...
Ko and Nakanishi organize a sandlot game with some old friends from elementary school. Ko stands on the pitcher's mound with Nakanishi as catcher. But after Ko throws a few practice pitches...
An unfriendly man comes to hit at the Tsukishima Batting Center. He hits homerun and homerun, and the other patrons are astonished. When a group of students come check out the high school, the homerun hitter is among them.
Aoba tries to make porridge for Momiji, but then Ko proceeds to skillfully prepare some food for Momiji, and the three of them end up spending New Year’s Eve together. And then, the cherry blossoms bloom and…
Ko, Akaishi and Nakanishi are starting high school, but under the new coach, only a few players make varsity. So Ko and the others join the Portables, the JV team who use a portable for a clubhouse. At the Jr. High, Aoba is the team’s new captain.
The coach invites Aoba to the team’s batting practice. When Ko, Akaishi and Nakanishi hear of it, they go over to confront Daimon. Aoba is getting warmed up when she starts striking out the varsity batters. But when Azuma steps up, she may be too tired...
Aoba feels disgruntled when she hears that Momiji has gone to the park with Ko. Meanwhile, Coach Daimon and the principal discuss the baseball teams' futures. Daimon declares he has no intention of bringing any of the Portables up to varsity, but...
It’s the Portables vs. varsity! Ko takes the mound in the bottom of the first. He uses Aoba’s notes to his advantage and strikes out the first two batters, but later in the game, Azuma hits a home run off of him. And Senda...
Ko hits a triple off of Kamikawa's fastball, but he’s getting more and more exhausted. With his fatigue at its peak, Ko tells Akaishi that he’s going to forget about control and focus on speed.
The seniors on the Portables start sulking when they realize they have no shot at joining varsity, and their unmotivated playing drags the whole team down in the scrimmage against the varsity team.
Ko and Senda visit the junior high to watch the scrimmage game. Aoba is pitching, and she’s so in control she purposely lets the batters get a few hits.
The district tournament begins, and the varsity team sweeps their first opponent. Azuma’s getting a lot of attention from the media, but he and Miki start to have misgivings about Coach Daimon.
Daimon's irrational coaching leads to a loss for the varsity team in the district tournament. Aoba meets Azuma’s brother Junpei at the game and takes him home with her, where he immediately falls in love with Ichiyo.
The Portables' not-so-stellar record has the principal thinking it's the perfect chance to get rid of the Portables and fire Coach Maeno. But Coach Maeno challenges Daimon's team to a scrimmage...
The varsity team and the Portables face off in a critical match. Ko gets off to a shaky start on the pitcher’s mound, loading the bases with the first three batters. The two coaches have bet their jobs on the outcome.
The Portables triumph over varsity, and Coach Daimon and the interim principal leave the school, along with some of Daimon's recruits. Azuma decides to stay at Seishu Gakuen High.
Risa has stayed at Seishu Gakuen even though her father, the former interim principal, left the school. She causes some confusion when she practices for a movie audition.
The Kitamura and Tsukishima families visit Wakaba's grandparents, the Asamis. Ko and Aoba look through photo albums and reminisce about Wakaba.
Aoba starts high school at Seishu Gakuen. Her cousin, Mizuki Asami, starts there too, where he becomes the center of the all the girls' attention. But what really bugs Ko and Azuma is that Mizuki is moving in with the Tsukishimas...
There is a rumor going around that Aoba and Mizuki are dating. But Mizuki is jealous of Ko's relationship with Aoba. Meanwhile, Seishu's baseball team raises the intensity with their new members.
Midori asks Aoba to play on an all girls' school baseball team in an upcoming game. But Aoba feels like she should stay true to Seishu Gakuen's team and decline.
Aoba plays on Midori's team against a college powerhouse, but she is put in center field. The college team is strong on offense, and it looks like it could be a blowout. But then, Aoba takes the mound..
Ko and his teammates watch one of the nation's best teams scrimmage. They are all captivated by one player on the team, Keitaro Mishima, whom Azuma remembers from Senior League.
Seishu Gakuen advances to the second round of the summer tournament. But their opponent collects a lot of information on Seishu and goes after their weak points. Will Ko's pitching be enough to win?
Sannou tries to tire Ko out by bunting. But despite all the data Sannou got on them, Seishu takes the lead with a home run from Nakanishi. Will they move on to face Ryuou Gakuin?
Ryuou Gakuin's ace Matsushima starts off with a bang, pitching a 1-2-3 inning. But Ko strikes back with three strikeouts in a row. The crowd goes wild, but Aoba doesn't seem amazed... yet.
The game between Seishu and Ryuou turns into a battle of pitchers. Seishu still leads 1-0 going into the top of the seventh inning, but then Mishima comes in for Shimano. How will Ko fare against him?
The game between Seishu and Ryuou goes into extra innings. Ryuou's pitcher looks fresh, since he only came in during the ninth. But will Ko be able to keep pitching as well as he has been?
Ko's new neighbor Akane looks exactly like Wakaba, which brings back a flood of memories to Ko.
The anniversary of Wakaba's death is also the day of the summer festival. After visiting Wakaba's grave, Ko goes to the festival with Akane. Everyone notices how much she looks like Wakaba.
Akane finally moves next door to Ko, and Aoba doesn't like the fact that the two are becoming good friends. But one day, a certain incident brings Aoba and Akane closer together.
Akane learns about Wakaba when she goes over to the Tsukishimas with a present for Aoba.
Ko and his friends ring in the New Year by visiting a shrine. But they find themselves chasing after a pickpocket that victimized Junpei and Ichiyo.
It's Valentine’s Day, and the boys are comparing how many chocolates they received.
Aoba decides to try out for the national women's baseball team. The tryouts bring back memories of the painful loss against Ouka Women's University.
During practice, a ball batted by Azuma hits Aoba in the leg so hard that she is hospitalized. Aoba has to pull herself out of the women's baseball tryouts, and Azuma is wracked with guilt.
Ko goes on a date to a kabuki show with Akane. After the date, Ko goes to Akaishi's house to tell him all about the date. Then, he hands Akaishi a present from Akane…
Ko masters the breaking ball that Aoba taught him, and he tells her that she can pitch vicariously through him. Café Clover decides to hire a part-timer, and Akane is the first to apply.
Aoba gets a call from the national women's baseball coach with an unexpected invitation. Meanwhile, Ichiyo tells Junpei her one condition, which drives Junpei to coach Seishu as hitting coach.
Yuhei Azuma's brother, Junpei, comes on as Seishu Gakuen's hitting coach, and practice becomes more lively than usual. Meanwhile, Aoba and Akane become better friends.
The Seishu Gakuen baseball team gets a day off before their training camp begins. This year's summer tournament is especially important for Azuma, Akaishi, Nakanishi and Senda, as it is their last chance to aim for Koshien.
The summer tournament is nearing, and Azuma and Aoba run into Azuma's former coach, Daimon, who is currently coaching at a school that Seishu may face in the second round of the summer tournament!
Miki's team beats Daimon's school and advances to face Seishu Gakuen in the second round of the tournament. Ko gets nervous about facing Miki, but performs well on the day of the game.
Seishu Gakuen advances to the third round. Everyone on the team has been improving, including Ko, whose pitches seem to gain speed every game.
Aoba and Akaishi visit Akane in the hospital to tell her of their victory in the quarterfinals. There, they find out that she has made plans for a date with Ko.
Ko visits Akane in the hospital and finds out that she is to undergo an operation on the day of the tournament final. Ko tells Aoba, and they pray to Wakaba for a successful operation before heading into the final game.
It's the day of the district championship game between Seishu Gakuen and Ryuou Gakuin, but Aoba is not at the stadium, choosing instead to be at the hospital for Akane's surgery.
In the bottom of the seventh inning, Ryuou Gakuin is down by one, and Mishima comes up to bat with two outs. Ko can afford to walk him?
Thanks to Ko, Seishu has earned a one-run lead in the twelfth inning, but pitching eleven innings is starting to take its toll on Ko.
