whut?
RR was already the 135 champ at SF, prior to Zuffa's purchase.
Zuffa bought Strikeforce in March of 2011. Rousey debuted in King of the Cage at the end of that month. She would not win the title for another year.
A lot of people forget Strikeforce only was trying to be a national level company for around 18 months until they were sold. It was barely around.