Christina Aguilera had no problem showing off her 20 pound weight loss during "The Voice" season finale. All eyes were on the "Beautiful" singer as she performed her hit new song "Feel This Moment" with rapper Pitbull, the Daily Mail reports.

 The 32-year-old proudly showed off her toned tummy and slim figure in a tight bodycon skirt and sheer crop top as she made her debut return to NBC's singing-competition show. Aguilera, who is a judge on the show, took a slight hiatus to focus on her music career but will be back critiquing contestants for season 5. The singer had made headlines for her reportedly 40 pound weight gain after her 2010 divorce from husband Jordan Bratman.

A source close to Aguilera told US Weekly that the singer decided to use her break from the show to not only work on her music but to drop a few pounds.

"A lot of people were on her about her weight and it depressed her," the source told the magazine. "She went through a bad time because of the criticism."

Reportedly Aguilera signed up for a Fresh Diet program, a 1,600 calorie-a-day plan that allows her to choose form a variety of nutritious food options. She also is said to have teamed up with fitness guru Tee Sorge who helped her get in shape for her role in the movie "Burlesque." She has also been doing been yoga on a regular basis.

"She did it all on her own. She goes online and picks out her food," the source said. "It's more of a mind-body thing for her. She believes in exercise that she enjoys, doing strength work as opposed to intense cardio."

Regardless of what size she is, Aguilera told Marie Claire an interview that she loves her body and that is the most important thing to her.

"I've been criticized for being on both sides of the scale. It's noise I block out automatically," she told the magazine. "I love my body. My boyfriend loves my body. My son [4-year-old Max] is healthy and happy, so that's all that matters to me."

Aguilera will be heading back to "The Voice" for season five after briefly being replaced by Shakira.

Country singer Danielle Bradbery, 16, was crowned as winner on the season finale with Michelle Chamuel finishing in second and the Swon Brothers finishing in third.