United States Champion Kalisto faces a new gigantic challenger when he battles former U.S. Champion Rusev at WWE Extreme Rules. Tom Phillips broke the announcement today during a Facebook Live interview with Kalisto.

The Bulgarian Brute earned the championship opportunity by being the last man standing in a No. 1 Contender’s Battle Royal on the May 2 edition of Raw. While Superstars like Baron Corbin, Dolph Ziggler, and former League of Nations cohorts Sheamus and Alberto Del Rio were thrown to the wayside, Rusev endured the multi-Superstar brawl and ousted runner-up Zack Ryder for the win.

After securing his place as the No. 1 contender, Rusev vowed to win back the title that he contends rightfully belongs to him. (Let it not be forgotten that The Bulgarian Brute did, after all, dominate the division for five months starting in late 2014, mocking America while holding its namesake title captive.) Days later, in a sitdown interview with Michael Cole, Rusev took his vitriol to another level, promising to eat Kalisto's "big heart."

Yet, to suggest Kalisto has been anything other than a fighting champion would be a grave mistake. Since capturing the stars-and-stripes title, The King of Flight has fearlessly defended it against any competitor who comes his way, no matter the size. Can his streak against bulldozing superheavyweights continue when he meets Rusev at WWE Extreme Rules?

Find out when WWE’s most lawless event of the year takes over the award-winning WWE Network live on Sunday, May 22, at 8 ET/5 PT.