Notre Dame linebacker Manti Te'o acknowledged in an interview with Katie Couric that he briefly lied about his online girlfriend after learning she was fictitious.
Portions of the conversation with Couric for her syndicated television show aired Wednesday on ABC's "Good Morning America." The entire interview, his first on camera since news of the hoax came to light last week in a report by Deadspin.com, will air Thursday.
WATCH: Te'o talks with Katie
Te'o said he didn't lie about the existence of Lennay Kekua, the woman he believed to be his girlfriend, until December. That's when he claims he learned of the hoax when he received a call from a woman claiming she was Kekua, who Te'o thought had died of leukemia in September.
"Katie, put yourself in my situation," he said. "I, my whole world, told me that she died on Sept. 12. Everybody knew that. This girl, who I committed myself to, died on Sept. 12."
He also said he had no part in the hoax.
"Now I get a phone call on Dec. 6, saying that she's alive and then I'm going be put on national TV two days later (at the Heisman Trophy ceremony in New York). And to ask me about the same question. You know, what would you do?"
In interviews during the fall, Te'o had said he believed his grandmother, who died in September, and Kekua were watching over him.
Te'o's father, Brian, defended his son in the interview with Couric, saying the Heisman runner-up wasn't using the story for personal gain. "People can speculate about what they think he is. I've known him 21 years of his life. And he's not a liar. He's a kid."
In an interview Wednesday on NBC's "Today" show, the woman whose face was pictured on the Twitter account of Kekua said Ronaiah Tuiasosopo admitted to her that he was behind the scam. Tuiasosopo, who went to the same high school as Diane O'Meara, used the picture without her consent.
"I've never met Manti Te'o in my entire life" O'Meara said. "I've never spoke with him. I've never exchanged words with him."
In an interview with ABC News, Tuiasosopo's former football coach, Jon Flemming, said Tuiasosopo wishes "everyone would go away."
He's "somebody I'd want my kid to grow up like," Flemming said. "He's responsible, respectful, disciplined, dedicated."