Off the glass alley-oop question

I don't what I'm doing wrong. I did what the controls are saying. Alley-oop + trailing teammate. But it never throw a ball bounce off the glass to my trailing teammate. Thus, it only throws the ball mid-air just like a regular ally-oop. Clutch + fake pass right? Thanks,

yep, you got it right, it's just a matter of timing and position of the dunker

you cant do it in practice or freestyle mode, FYI

I'm hoping that Earl Boykins is not the trailing teammate but yeah JaoSming, is right, its all about timing and position of both passer and dunker.
Also Dunk, Hands, Speed rating of the trailing team mate are very important for the off the glass alley-oop to be successful.