Bruno Tonioli dropped the F-bomb while critiquing Erin Andrews and Maksim Chmerkovskiy on Monday night's Dancing With the Stars.
After Andrews, 32, slightly stumbled at the end of her paso doble, Tonioli snapped at Chmerkovskiy, "You were the one who f--ked up!"
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After the audience gasped, Tonioli said, "Oops, sorry."
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The show hastily bleeped out the swear on the live telecast.
Joked host Tom Bergeron, "Hey, that's what the censors earn their money for."
Chmerkovskiy told Us after the show, "There was a knee drop and I lost my balance. I didn't want the judges to comment -- but then Bruno cursed!
Joked Andrews, "There's a lot here for him to catch! And then Bruno also gave us a 10 when he wanted to give us a 9! He's out of control!" (The judge accidentally held up the wrong paddle.)
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Nicole Scherzinger (Argentine tango and cha cha) and Evan Lysacek (fox trot and paso doble) tied for first place, with scores of 59 out of 60 each for their two dances. Andrews came in second with 56 out of 60 for her Viennese Waltz and paso doble, and Chad Ochocinco was in last place with 52 out of 60 for his waltz and samba.
During the commerical break, the entire audience sang happy birthday to Scherzinger's partner, Derek Hough, who turned 25 that night. Scherzinger's family brought Hawaiian leis to celebrate.
Ochocinco told Us it was "fun" dancing without his shirt, which his partner, Cheryl Burke, ripped off mid-performance.
"I felt a little cold draft but it was all good!" he quipped.
Said Burke, "If I said take your pants off, he would. He is very comfortable in his own skin!"