The phrase "major precursor" refers to something that happens or exists before another important event or development. It is an important factor or element that contributes to the occurrence or success of something else. Full definition
It seems like every single day now there's a new major precursor announcement, doesn't it? (hollywoodnews.com)
Just a few short minutes ago this morning, the Screen Actors Guild unveiled their 2015 awards nominations, giving us the first major precursor to really sink our teeth into. (hollywoodnews.com)
The Broadcast Film Critics were the only major precursor group to recognize her, but she does have a few more notices to go along with that big one. (screenpicks.com)