Neither Carroll nor USC athletic department officials could be reached for comment.
Carroll had been scheduled to spend today in Richmond, Va., watching his daughter and the rest of the USC women's volleyball team play in a Final Four match against Wisconsin.
Sources close to the situation said the former NFL coach--who has said he wants the job--was summoned to Southern California from his Massachusetts home because he is now the leading candidate.
As early as last weekend, visiting his father in the San Francisco Bay Area, he expected to be hired.
"He had the idea it was all set," Jim Carroll said. "He was very excited about the possibility."
Carroll, 49, was running behind San Diego Charger Coach Mike Riley but Riley has been entangled in contractual obligations to the Chargers and his own second thoughts about leaving San Diego.
The Charger coach, who still considers himself in the running, said he spoke with a USC official Wednesday but said he was not offered the job.
Another oft-mentioned name, Colorado State Coach Sonny Lubick, said he was not expecting to hear back from USC unless the other two candidates fell through.
Wednesday's developments capped the wildest day, by far, in an already hectic two-week search.
After a mostly quiet afternoon, CBS SportsLine.com ran a story that USC was set to hire Carroll.
Within an hour, however, a San Diego television station broadcast a report that Riley was going to be fired by the Chargers. That led to immediate speculation he would go to the Trojans.
The NFL coach was in a meeting with his staff at the time. He emerged for a dinner break and phoned his wife at home.
"She asked me if I'd been fired," he told KFMB (760). "That was the first I'd heard of it. I thought she was kidding."
Shortly thereafter, the television station retracted its report and Riley was on the radio assuring listeners that he would remain with the Chargers at least until the end of the season.
But when asked if he would withdraw himself for consideration for the USC job, he balked.
"I think it's important just to let this thing play out," he said. "I guess I'm not willing to do that."
Riley's reluctance to count himself out says as much about the eventful search as it does about him.
USC began looking for a new coach after firing Paul Hackett more than two weeks ago.
In the first few days, USC Athletic Director Mike Garrett pursued Oregon State Coach Dennis Erickson, who subsequently signed a contract extension to remain with the Beavers.
Next came Oregon Coach Mike Bellotti who, similarly, signed an extension to stay put.
Riley became the next hot prospect and was expected to be a quick hire. But there were questions about whether he could get out of the final three years of his Charger contract and, as the days passed, he began to have second thoughts about uprooting his family.
Charger President Dean Spanos took a hard stance in public, saying he would hold Riley to his obligation. In private, he was reportedly willing to let his coach go after the Chargers played their final game of the season against the Pittsburgh Steelers on Dec. 24.
But Riley wondered aloud if USC--with the crucial recruiting period ticking away--would wait that long.
Wednesday he seemed prepared to accept any outcome, saying, "I'm at peace with whatever goes on."
Meanwhile, the focus had shifted to Carroll.
Partly he stayed to watch his daughter, Jaime, and her team in the volleyball playoffs. But he also attended a high school football game and introduced himself to two USC football players watching from the sideline.
Reached at home on Tuesday, he said of his negotiations with USC: "There has been strong mutual interest. It's a pretty hot topic right now. I'm looking forward to seeing what the outcome is."
Carroll began coaching at his alma mater, Pacific, in 1974 and worked his way through a series of assistant jobs at schools such as Ohio State and North Carolina State before moving to the NFL.
Known as a defensive specialist, he worked his way up to becoming head coach of the Jets for the 1994 season, then had a three-year stint with the Patriots in the late 1990s.
His record in the NFL is 34-33 with two trips to the playoffs.
That experience might not sit well with some Trojan fans if only because Hackett also came to USC from the NFL. Even Garrett said, at the beginning of his search, he would prefer someone with a proven record in college football.
Carroll's last job in college was as a Pacific assistant in 1983.
His father said, a year after being fired by the Patriots, Carroll was looking toward the college game for a new start.
"He liked the pros but he didn't want to be a defensive coordinator again," Jim Carroll said. "He wanted to go to a place where he had a chance to win. He feels he has a great chance to win [at USC]."
Staff writer Sam Farmer contributed to this story.
Instead of the expected off-tackle play, USC Athletic Director Mike Garrett appears to have called a reverse. D2
LIFE OF RILEY
Charger Coach Mike Riley weathered a day of twists and turns regarding his future with the team. D10