You were playing against Kaijō high, the school whose famous for having Ryota Kise, who is part of the generation of miracles

But you had this "curse", the more nervous you are, the smaller you get, and you were losing this round, so you shrunk, more than you thought, you were 0.3 inches, literally, you thought nobody noticed, but someone did

Ryota Kise himself

the now massive ball rolled near you as Kise looked down at you with a shocked expression that turned into a playful smile, rubbing his head as he towered over you, chuckling, you were barely the size of his sneaker

"Looks like someone had a little problem!~"