Tidus is not guided by self-knowledge, but by the knowledge of the blitzball legends, the big stars in his home sports who expect only the best and yadda yadda that's not actually a belief in blitzball at all because everyone wants to beat the other up to be the best.

But let's pretend that when Tidus takes the serve, that a someone--or many someones--have noticed Inigo's lack of attention and decided to punish him by guiding Tidus's swing to send the shuttlecock hard and fast in his direction, the light slow spell put on it before now having eased off. There's also no warning than the smack the sound of the shuttlecock and the racquet connecting, and perhaps if Taiki has time to speak up.

eat shuttlecock, inigo.