Video: From 'friends' to 'f-ck em,' ATT and Blackzilian fighters talk 'TUF' rivalry

“The Ultimate Fighter 21? kicks off this week, and the latest edition of the long-running series will, for the first time, focus on a rivalry between two gyms rather than two fighters. But just how real is the tension between the two camps? We asked fighters from both gyms to find out.

“It’s going to be a roller coaster of a show, and I’m not just saying that,” American Top Team featherweight Nik Lentz said. “We broke ‘The Ultimate Fighter.’ After this season, there’s nothing that’s going to be like it.

“There’s never been a rivalry like this. There’s never been this type of atmosphere in the gym and the fights and stuff, and I guarantee you after this season of ‘The Ultimate Fighter,’ it’s going to be a double-edged sword because it’s going to be the best one, but after that, there’s no coming back.”

Based in Florida, American Top Team and the Blackzilians are only separated by about 10 miles, and the latter team was created when fighters from the former camp decided to jump ship. As such, there are friendships that still exist between some of the fighters, though team heads Dan Lambert and Glenn Robinson are anything but cordial.

But once the teams were herded into one location and pitted against each other, Blackzilians fighter and former UFC light heavyweight champion Rashad Evans said the rivalry came into full focus.

“The tension was so thick, if someone would have threw a water bottle, it would have been just like a straight up war in that place,” Evans said. “It would have been just bedlam.”

“The Ultimate Fighter 21? debuts Wednesday at 10 p.m. ET (7 p.m. PT) on FOX Sports 1.

To hear more from American Top Team’s Thiago Alves, Lambert, Lentz and Daniel Straus – including one who describes the relationship with a pointed expletive – as well as from the Blackzilians’ Gesias Cavalcante, Evans, Michael Johnson and Abel Trujillo, check out the video above.

For more on the UFC’s upcoming schedule, check out the UFC Rumors section of the site.