Julianne Hough Returns, Guest Judges on 'Dancing With the Stars'

Julianne Hough was back at her old stomping grounds Monday night to guest judge "Dancing With the Stars," and the dancer turned singer and actress earned rave reviews.

"It was great she did a really great job and I was really proud of her," Derek Hough, Julianne's brother who is also a pro dancer on "DWTS," told E! Online after Monday's episode.

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Hough, 25, got her start as a professional ballroom dancer and then segued to country music and film over the last five years. Her self-titled debut album debuted at No. 1 on the Billboard Country charts in 2008, and she received praise for her role in the 2011 remake of "Footloose" and 2012's "Rock of Ages."

She won the fourth and fifth seasons of "Dancing With the Stars" back-to-back in 2007 — first with celebrity partner speed skater Apolo Anton Ohno and then with Brazilian auto racer Helio Castroneves.

Hough reiterated throughout Monday's episode that she wanted to provide the celebrity contestants with constructive criticism, but she did take a little shot at pro Mark Ballas during the critique of the foxtrot he performed with singer Christina Milian.

"I really wanted to see you shine," Hough told Milian, then paused. "I danced with Mark. You have to stand in front to make sure you’re seen."

Ballas later brushed off the zinger.

"She put a little sting on me, but that’s okay," he told reporters backstage after the live broadcast. "That's how she felt. It is what it is."

The night's top score was a three-way tie between "Saved By the Bell" alumna Elizabeth Berkley, "Glee" star Amber Riley, and Corbin Bleu from "High School Musical" — who all earned 27s.

Valerie Harper, who played Rhoda on "The Mary Tyler Moore Show," was eliminated after her Viennese waltz with pro partner Tristan MacManus failed to impress the judges. But the 74-year-old's courageous journey on the show inspired viewers, contestants, and judges alike.

Harper, who was diagnosed with a rare form of brain cancer earlier this year, told E! Online that her elimination was "a blessing in disguise."

"I'm sad to leave the group and the people, and the fun, the interactions and the challenges, but my knees are in bad shape," she said. "Not terrible, not that I need surgery, but they need a rest. These knees are 74 years old and they are barking."

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