Can I still be Admitted into the School?

[micromajor2011]

So I took it upon my self to email a POI at a school that I have applied too. To my surprise he asked me to set up an appointment to me with him. If I am able to "Wow" him and he offers me a chance to work in his lab, would I still need to do an interview through the school as well? Also would I still be admitted without doing another interview? Im only asking because this schools set-up is every grad student entering must do 3 lab rotations first, but If I pick one off the top and he offers me a place in his lab Im not sure how that would workout if that is even an option at this type of school. Just curious. Thanks for your answers and feedback!