Please anyone who can tell me about this manga

The manga I've been finding is about female childhood friend of the mc has a crush on someone who is a boxer(I don't remember if he is a champion or not)
She is a bit tomboy
MC want to help Female lead by helping her study but she gave up she broke the promise she has with the MC
I don't remember much after that but I remeber MC told her he love her but she reject him and tried to avoid him until he gave up his love in the end she regret it and want him back

I'm very interested in knowing that too, I also read that manga but forgot its name and didnt bookmarked.

All I remember is this that you already rote, and that the boxer name its MEGA ... something, my memory is really bad.[a]

Could be Sakurasaku Shoukougun.

~4400 manga completed
~1700 ongoing...