10/06/2013 05:03 BST | Updated 10/06/2013 05:20 BST

Jessie J Shrugs Off Illness To Perform In See-Through Dress At Capital Summertime Ball (PICTURES)

Jessie J wasn't going to let a sniffle get in the way of her putting on a show (and flashing some flesh) at the Capital Summertime Ball at Wembley Stadium on Sunday.

The singer looked like she was having a Ball as she took to the stage in a see-through outfit, which showed off her incredible figure.

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Jessie J

However, before the show she revealed on Twitter that she wasn't feeling quite as great as she was looking.

"Time to rest before glam time! I refuse to be sick! No no no sickness! You ain't gonna win! Muhahahaha!" she said.

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Jessie shows off her moves on stage

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Jessie was also joined on stage by B.o.B to perform 'Price Tag'

On stage, wearing a dress made of black mesh, Jessie belted out a string of her hits, and also treated fans to the first live performance of her new single 'Wild'.

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Jessie J poses backstage with Robbie Williams, who also played the gig

Jessie was also rocking her new shorn blonde 'do after shaving her head for Comic Relief in March, something which she recently hailed as one of the highlights of her career so far.

She told Glamour magazine: "Obviously, shaving my head was a massive highlight. I've been wanting to do it for a long time but I wanted to be famous enough that it would raise a lot of money."

See all the pics from the Capital Summertime Ball below, including Taylor Swift, Union J, The Wanted and Justin Timberlake...

Photo gallery Capital FM Summertime Ball See Gallery