Linford Christie suffered humiliation in the jungle after he lost a physical task to Stacey Solomon.
Stacey was certain she would lose the Bounce-A-Roo challenge to Olympic gold medal sprinter Linford.
The pair were told to dress up as kangaroos and squash rotten fruit with their feet.
The celebrity who produced the most liquid would win a night of luxury, while the loser would endure a night of terror.
Linford, 50, took the early lead in the I'm A Celebrity ... Get Me Out Of Here! challenge, but when Stacey, 21, decided to pick the fruit that squashed easily she overtook her rival.
She said afterwards: "We were so competitive... I don't think he was that happy I won... he was a bit of a sulk."
The X Factor star added: "I decided to go for tomatoes rather than bananas to produce more juice. The boys must have been thinking, 'Yeah, we've got Linford Christie, he's got mammoth feet!'"
A disappointed Linford confessed: "You whupped my a*s!"
He added: "My ego is bruised more than my bottom. I'm thinking, how do I tell the guys I've lost and will one of them come and spend a night of terror?"
Linford - and Aggro who volunteered to join him - had to spend an uncomfortable night in a cave with only a candle for light and the company of spiders and cockroaches, while Stacey selected Jenny Eclair to join her for the night of luxury.