Top of the crops! Witney Carson displays taut tummy in white midriff-baring blouse as she arrives at DWTS rehearsal

She was just announced as part of the new cast of ABC's Dancing With The Stars.

And Witney Carson let her presence be known on Thursday, as she arrived at rehearsals in Hollywood, California.

The 21-year-old star put her taut tummy on display in a tight white crop top detailed with perforated shoulders.

Showing off: Witney Carson put her taut tummy on display in tight white crop top as she arrived at Dancing With The Stars rehearsals in Hollywood, California on Thursday

Showing off: Witney Carson put her taut tummy on display in tight white crop top as she arrived at Dancing With The Stars rehearsals in Hollywood, California on Thursday

The blonde beauty paired her midriff-baring blouse with black high-waisted harlem pants and matching sneakers.

Her hair was styled up in a bun, and the professional dancer, who is dating Carson McAllister, wore a light palette of make-up.

Witney is partnered with Big Time Rush star, Carlos PenaVega, 26, who was seen arriving with his wife Alexa PenaVegas, 27.

Beauty: The blonde wore a light palette of make-up while wearing her tresses up in a bun

Beauty: The blonde wore a light palette of make-up while wearing her tresses up in a bun

Monochrome; The 21-year-old paired her perforated crop top with black trousers and matching shoes

Monochrome; The 21-year-old paired her perforated crop top with black trousers and matching shoes

Alexa will be competing with Mark Ballas, 29.

Carlos showed off his buff biceps in a sleeveless grey shirt which he teamed with black tracksuit trousers.

Mark was wearing similar trousers with a black T-shirt and matching high-top Converse shoes.

His hair was styled in a manbun, and he was seen carrying a guitar case while flashing a peace sign at onlookers.

Competitive couple: Alexa PenaVega, right, and her husband Carlos PenaVega are both competing 

Competitive couple: Alexa PenaVega, right, and her husband Carlos PenaVega are both competing 

Matching: The pair coordinated in grey blouses and black trousers
Matching: The pair coordinated in grey blouses and black trousers

Matching: The pair coordinated in grey blouses and black trousers 

Bindi Irwin and her partner Derek Hough were also spotted arriving at rehearsals.

The daughter of late The Crocodile Hunter star Steve Irwin looked chipper and ditched her signature khaki blouse for a brown T-shirt and cropped black leggings.

Derek appeared serious while dressed casual chic in a white T-shirt, Hawaiian-patterned blue button-down blouse, jeans, and blue sneakers.

High spirits: Bindi Irwin as all smiles as she arrived in a brown T-shirt and grey leggings
High spirits: Bindi Irwin as all smiles as she arrived in a brown T-shirt and grey leggings

High spirits: Bindi Irwin as all smiles as she arrived in a brown T-shirt and grey leggings

Meanwhile, it was revealed that Peta Murgatroyd, 29, will not be returning for season 21 of Dancing With The Stars.

New Zealand-born beauty confirmed that she will be sitting out DWTS while she recovers from surgery on her ankle.

She told People of the moment she received the shocking news via email: 'It was devastating news for me.

Casual chic: Derek Hough looked trendy in white T-shirt, blue Hawaiian-printed button-down and jeans
Casual chic: Derek Hough looked trendy in white T-shirt, blue Hawaiian-printed button-down and jeans

Casual chic: Derek Hough looked trendy in white T-shirt, blue Hawaiian-printed button-down and jeans

'I wanted to check it out properly and make sure I was good to go for the season. I Got my MRI results back and it was a really bad diagnosis. It showed I had 4 torn ligaments and a floating piece of bone at the back of my ankle.'

Peta was going to be teamed up with singer-songwriter Andy Grammer but will now be home recovering for six to eight weeks.

The pro - who has been competing on the show since 2011 - revealed she felt bad about disappointing the Honey, I'm Good hit maker, 'He had specifically asked to be partnered with me and I felt like I was letting him down,' she said.

Suave: Mark Ballas arrived with a manbun while clad in an all-black ensemble

Suave: Mark Ballas arrived with a manbun while clad in an all-black ensemble

Musician: The star flashed a peace sign while arriving with a guitar at hand

Musician: The star flashed a peace sign while arriving with a guitar at hand

'It's super frustrating but I'm going to be fine and I'm going to be back in week eight or nine of the show'

The full celebrity cast was revealed on Good Morning America on Wednesday morning.

Paula Deen, Kim Zolciak, Tamar Braxton, and train hero Alek Skarlatos will join previously announced stars Gary Busey, Bindi Irwin, Chaka Khan, Andy Grammer, Nick Carter, Internet sensation Hayes Grier, jockey Victor Espinoza, and the show's first married contestants, Alexa and Carlos PenaVega.

Season 21 of Dancing With The Stars returns September 14.

Recovering: It was announced that Peta Murgatroyd, right, will not be starring in the upcoming season of DWTS. She is pictured here with Maksim Chmerkovskiy, left, in July

Recovering: It was announced that Peta Murgatroyd, right, will not be starring in the upcoming season of DWTS. She is pictured here with Maksim Chmerkovskiy, left, in July