Introduction: There was an unlucky guy who traveled through time while sleeping.
What's even more unfortunate is that as soon as he time travels, he finds himself playing a tennis match that he doesn't understand at all.
The protagonist has a golden finger, there are competitions and the story is quite long.
In addition, this article summarizes the following anime
The Prince of Tennis, The Beautiful Boy in Black at the Crossroads, Conan, The House of Resentment, The Tutor, The Little Black Book, etc.
It is privately designed, so there is no guarantee that the characters will not be OOC.
Purpose: competition