The main lead is Eijun Sawamura and his start in the anime isn't a smooth one. He has a bit of raw talent, but he's certainly not viewed as a prodigy or a natural talent. When Eijun officially starts high school and is on the team, he's basically the last pitcher on the depth chart and is actually originally very close to not even being on the team.
2. There's competition not just with other teams but amongst the team.
We don't just see the Seido baseball team face other teams. There's even players facing off against each other for a spot on the roster. Eijun's biggest rival isn't a pitcher or hitter on another team, but a pitcher on his own team. Furuya comes in as the exact opposite of Eijun. He has the natural talent and is even considered a "monster rookie" when he makes his debut. Eijun is constantly facing off against Furuya to move up the depth chart and get to his ultimate goal of becoming the ace.
3. True camaraderie amongst the team.
There's not just competition amongst the team, but also a lot of camaraderie. Players are constantly taking shadow swings together and helping each other practice at all hours of the night. While Eijun and Furuya are technically each other's biggest rivals, they also both push the other to be better. One of the largest turning point in the series was when Eijun had to overcome the yips. The current players and even a past catcher that he developed a good relationship with, rallied around him to help him get past this.
4. Easy to root for the other teams.
There are SO many teams we get to see throughout the anime. We see Inashiro with Narumiya Mei who comes off as a complete brat, but actually has a strong sense of responsibility as the ace of Inashiro. There's a team once considered a dark horse in Yakushi, with a funny manager and players like Raichi who only thinks of swinging his bat. Then there's Amahisa with Sankou, a pitcher who originally decides to quit the team on a whim, but after seeing them suffer a devastating loss, decides to return to the team and give it his all. He also develops a funny but lovable relationship with Eijun.
5. BROMANCE
Sawamura and Chris have one of my favorite bromances ever. Chris starts out dejected as he's dealing with injury that has really derailed his baseball career. He clearly sees Eijun as a brat and isn't the warmest towards him. In turn Eijun is disrespectful towards him and doesn't care to listen to any of his advice. With Miyuki intervening, this all changes and you can literally see how Eijun helps Chris light up again. Chris becomes someone Eijun really respects and wants to impress, even showing a lot of emotion when Chris graduated. Miyuki and Kuramochi come in a close second. Although they claim to not be friends, they spend all their time even off the baseball field hanging out and bickering. Kuramochi also seems to worry when Miyuki is at odds with another player on the team and doesn't seem to take offense to any of Miyuki's harsh jokes.
Ultimately, Ace of the Diamond has it all when looking for a sports anime. While baseball may not be everyone's sport of choice, the series transforms every game into a high-stakes emotional battle. Between its memorable cast, intense rivalries, strong themes of teamwork and perseverance, and the growth of characters like Sawamura, it's easy to become invested in Seido's journey.
