Donald Trump (search) had a message last night for fellow reality-TV moguls Richard Branson (search) and Mark Cuban (search): You're fired!

The Donald took aim at the two billionaires as he lectured the losing team last night on "The Apprentice."

His remarks about Cuban and Branson, who each starred in his own short-lived business-world competition show, were meant to underscore a point about one contestant's lack of fighting spirit.

That contestant — folksy, bow-tied attorney Bren Olswanger (search), 32, of Memphis — was fired moments later by Trump, who felt Olswanger was not being aggressive enough in defending himself against comments made about his performance by his last remaining teammate, attorney Alex Thomason, 29.

"Branson went after me — I killed him!" Trump declared. "Cuban went after me — I killed him!"

Branson, the founder of Virgin Group, was the star of "The Rebel Billionaire" on Fox. Cuban, who made a fortune from the Internet boom of the 1990s and now owns the Dallas Mavericks, starred in "The Benefactor" on ABC. Both shows are now defunct.

Trump, whose series is one of NBC's most popular shows, has long considered both men to be pretenders to his throne.

Reached last night by phone, Cuban laughed uproariously at Trump's latest salvo, and then offered an off-color response that was partially unprintable.

"Donald needs to stop drinking his own Kool-Aid," Cuban said mischievously. "He's getting sick on himself!"

Branson could not be reached for comment.

Olswanger was canned following a challenge in which the two "Apprentice" teams were assigned to create a new desktop storage unit for Staples, the office-supply chain.

Olswanger and Thomason's effort got a thumbs down from Staples execs. It was the ninth consecutive loss for the hapless Net Worth Corp.

Four contestants are left on "The Apprentice," which has its season finale on Thursday, May 19.

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