Pink at the Super Bowl . Picture: Bang Showbiz

Pop megastar Pink had to defend spitting out a throat sweet at the Super Bowl on Sunday after several Twitter users claimed it was a piece of gum the singer threw onto the football pitch.

The 'What About Us' hitmaker was spotted on camera removing something from her mouth on the pitch before singing a rendition of the American national anthem, 'The Star-Spangled Banner', and several Twitter users criticised the pop star for throwing what looked like gum onto the ground.

However, Pink - whose real name is Alecia Beth Moore - fired back insisting it was a cough sweet as she was known to be battling the flu.

She simply wrote: "It was a throat lozenge (sic)"

The 38-year-old star also defended her performance at the U.S. Bank Stadium in Minneapolis after one user said she "sucks".

The 'So What' singer snapped back: "Yeah but at least I suck while singing our countries national anthem, and you just suck by yourself on a dirty couch. #winning (sic)"

Pink blamed her children, Willow, six and Jameson, 13 months - whom she has with husband Carey Hart - for making her sick in the run up to the televised football spectacle. 

She shared a picture of herself rehearsing on Instagram and wrote: "Trying to practice the flu away. I've been waiting to sing this song since 1991 when I saw my idol, Whitney Houston, own this song. And now, my chance has finally come. And it just so happens that this chance comes when I have two small Petri dish kids who literally cough INTO MY MOUTH and rub their snot on my cheek..."

The national anthem has previously been sung at the Super Bowl by the likes of Lady Gaga, Idina Menzel, Alicia Keys, Billy Joel, Diana Ross, Neil Diamond, Whitney Houston, Luther Vandross, Cher, Faith Hill, Mariah Carey, Beyoncé and Christina Aguilera.

Watch Pink perform the national anthem at the Super Bowl below: