The pair were both sent home by Lord Alan Sugar after losing a task that involved negotiating discounts for a daily deals website, leaving Ricky Martin the sole survivor of Sterling.
The team, overseen by Brady as part of a deal he made with the ex-Amstrad boss last week, had three of their nine offers put live on the site, raking in a total of £6,440. However, the Jade Nash-led Phoenix earned £14,563 from two of the six deals they obtained.
In the boardroom, Martin received blame for wasting time at a restaurant that ultimately refused to negotiate and convincing Brady to cancel an appointment at a distant but luxurious spa.
However, Omar was criticised for championing a 'fish spa' deal when they had been told to collect high-end experiences, and both she and Brady were accused by Lord Sugar of "running around like a couple of headless chickens".
Karren Brady later told him they had been "as bad as each other" on the task, saying: "It was unstructured, it was chaotic and it lacked any sort of direction."
When all the candidates were brought back, Sugar told Martin he had made "a very, very serious mistake" with his "belligerent decision" not to go to the spa. He also noted that he could detect "an air of panic" in Brady's performance.
Despite the comments, Sugar first decided to fire Omar, telling her: "I don't think you contributed much in this task at all, to be honest with you.
"I'd just like to reiterate that it's the person who I feel is most responsible for the lack of contribution in the task that leaves, and on that basis I've got to say that Gabrielle, as nice a person as you are, it is with regret that - you're fired."
Speaking after her firing, the 29-year-old architect revealed: "Plans for me now are really just to get to grips with the businesses I already have and to make them a success and show everyone that behind this smile there is a brain and I'm going to go far in life."
Once Omar had left the boardroom, Sugar reminded Brady of his promise last week that he would lead Sterling to victory.
"There's no smoke without fire, Stephen," he started. "You asked me for the chance to be the project manager, I gave you the chance. You told me you were going to win, you didn't win, you lost. I think on that basis I've made a decision, and that is that - you're also fired."
The Apprentice continues Wednesdays at 9pm on BBC One.
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