The Donald says he knows why his version of "The Apprentice (search)" is hurting in the ratings this year: Martha Stewart.

"I think there was confusion between Martha's 'Apprentice' and mine," Donald Trump (search) told ABC News Radio yesterday.

"And mine continues to do well and, as you know, the other one has struggled very severely.

"But I think it probably hurt mine, and I sort of predicted that it would because there was a lot of confusion [with] people that wanted to watch 'The Apprentice.'

"And a lot of people were even upset that this was done. But I really feel that there was a certain amount of confusion which hurt the original 'Apprentice,' " Trump said in an interview with ABC (search)'s David Blaustein that airs today on its national radio network.

Last year, at this point in the season, Trump was averaging about 16 million viewers a week. This year he's pulling in about 10 million. The Martha version is averaging about 6.6 million viewers.

"Apprentice" creator Mark Burnett says that putting the shows on two nights in a row each week — Martha on Wednesdays and Donald on Thursdays — was a mistake and has essentially split the audience.

"In hindsight, two nights in a row each week is hard to invest in [for viewers]," he said. "Thirty-two characters are a lot to follow in this format." Burnett said he expects the ratings to grow as each program builds to its season finale.

Trump said that no decision has been made yet as to if Stewart's version will get a second season, but hinted that it might be an uphill battle.

"Well, that's up to really Mark Burnett and myself and NBC (search) as to whether or not the Martha show continues, but it certainly has struggled mightily," Trump said.

Burnett said he hasn't even talked to NBC yet about bringing back the Martha edition. "There's no urgency," he said.