“The Ultimate Fighter” Season 18 coaching lineup underwent a significant change this past week with the announcement that unbeaten rising star Cat Zingano (8-0 MMA, 1-0 UFC) had withdrawn from the competition due to a torn ACL. Zingano had been scheduled to coach a team of male and female fighters against UFC women’s bantamweight champion Ronda Rousey (7-0 MMA, 1-0 UFC), but the knee injury will sideline Zingano until 2014. Zingano earned her “TUF 18″ coaching position by stopping former Strikeforce champion Miesha Tate (13-4 MMA, 0-1 UFC) in April. With Zingano injured, Tate stepped in to take her place and surprised Rousey when she showed up for the first day of filming this past Tuesday. Rousey, who had not been informed about the coaching change, was reportedly shocked and upset because she initially believed that it was she who had been replaced. After confirming that her spot on “TUF 18″ was safe, Rousey began to warm up to the idea of coaching against Tate. The arch rivals will face off for a second time later this year, and Rousey’s UFC title will be on the line. Rousey became the final Strikeforce women’s bantamweight champion in the pair’s first meeting in March 2012 when she submitted Tate with a gruesome first-round armbar