 If you liked
Diamond no Ace
|
 ...then you might like
Yugami-kun ni wa Tomodachi ga Inai
|
Both series have baseball in it and are one of my personal favourites. I think both series exceed at writing characters and their relationships. However, while Diamond no Ace has their characters focus on entirely on baseball, Yugami series the characters have other goals and interests in life as well.
Both are great series in their own special way.