It is obvious that many people, especially UCLA fans, do not understand the significance of the term backing in . It refers to the manner in which a team clinches the championship, playoff spot, Rose Bowl, etc.
Last year, USC clinched the Rose Bowl victory by beating Washington. This year, UCLA did not control its own destiny. The Bruins did not clinch the Rose Bowl until Arizona State lost to Arizona. The Bruins' destiny was controlled by the Arizona teams.
I hope I have explained this simply enough for UCLA fans to understand.