Casual: Wow, Britney Spears totally rocked that leather minidress at The X Factor viewing party at Mixology 101 in Hollywood last night. She looked absolutely radiant!

Ouch: Poor Britney's ankle looked very sore as braved the red carpet in the highest of heels

Ouch: Poor Britney's ankle looked very sore as braved the red carpet in the highest of heels

Oh dear, Britney’s ankle appeared to be quite painful as she bravely walked the red carpet in sky-high heels.

Ouch: Just occasionally Britney winced a little as she stood on the carpet in her high shoes

Ouch: Just occasionally Britney winced a little as she stood on the carpet in her high shoes

Occasionally, Britney would wince while standing on the carpet in her high heels. The discomfort was evident on her face.

Flawless: Britney looked radiant and struggled through her appearance with the painful ankle

Britney shone with radiance although she had to put up a brave front due to her painful ankle.

Support: Britney was flanked by her fiance Jason Trawick at the ritzy event

Assistance: Britney was accompanied by her betrothed Jason Trawick at the posh occasion.

Sharing a giggle: Britney smiles with Simon

Having a laugh: Britney grins alongside Simon.

Moment of truth: Britney lost Diamond White (right) but held on to Carly Rose Soneclar (left) is in the last four

The moment has arrived: Britney Spears said goodbye to Diamond White (on the right) but decided to keep Carly Rose Soneclar (on the left) in the top four.

On her feet: Britney spent most of the night doing her X Factor judge-ly duty

Britney was busy fulfilling her duties as an X Factor judge throughout the night.