Question about macros

[Vyalkuran]

So i'll keep it short, is there any function that allows me to delay a /cast function until another spell has been cast?
For example
/castsequence Fire Elemental Totem, Feral Spirit
/cast Elemental Mastery

So, what should i write in order for Elemental Mastery to be cast ONLY after the castsequence has been cast? cause in the state i wrote up there, it would mean that it firstly casts fire elemental totem but at the same time it also casts elemental mastery, before feral spirit, which i don't want in this situation. Thanks in advance.