Didier Cohen and Deni Hines joined Jesinta Campbell and Shane Crawford in Team Unity, while Max Markson and Polly Porter teamed up with finalists Julia Morris and Jason Coleman in a task to create an advertising campaign for boss Mark Bouris's wealth management company Yellow Brick Road.
Crawford chose Cohen to join him and Campbell, further igniting rumours of a romance between the modelling duo by referring to Cohen as Campbell's "boyfriend". He later called them "lovebirds" and revealed that Cohen is "starstruck" by the former Miss Universe Australia.
Cohen jumped to Campbell's defence when she clashed with Hines during the task, saying: "It's the Deni Hines show. It's like we're interrupting her set." He referred to the singer as "super defensive" and "super aggressive".
After Hines snapped at Campbell: "Take a back seat and watch me work," the model said: "This isn't about us, it's about charity. She just wants to fight with me. She's out of control!" Hines then said: "Honey, you need to step away from this vehicle before I go off like a scud missile. You think the world owes you something."
Campbell hit back that she "can't deal with people who behave like children" and criticised Hines for her bad attitude, only to be threatened by Hines saying: "I might do something to you where you might never model again."
Onlooker Crawford later told the cameras: "You could cut the air with a knife. It was so intense." Hines has previously fallen out with The Block winner Porter.
In next week's final episode, each team's campaign will be revealed and the winner of Celebrity Apprentice 2011 will be announced.
The final of The Celebrity Apprentice Australia airs next Monday (November 21) at 7pm on the Nine Network.
> Pauline Hanson hits out at 'Celebrity Apprentice' co-stars
> Julia Morris posts 'Leave Britney alone' parody vid for Jason Coleman