But Bill Squires, a sports facility consultant, was not persuaded anyone was to blame.

"I would be very reluctant to ever point a finger, knowing what I know now, at an individual; I just think it was one of those things," he said. "I've got to believe that those guys do the preventive maintenance."

Besides, Squires said, the outage was no more than an inconvenience. "Nobody got hurt; everybody was safe."

And James Fama, vice president for energy delivery at the Edison Electric Institute, said the system appears to have worked well, given that the lights came back on and the circuitry was not damaged.

"The bottom line for any utility or any electric planner would be -- protect your equipment so that you can re-energize it. And it appears to be exactly what happened."

CBS, citing ratings figures from The Nielsen Company, said Sunday's game between the 49ers and the Ravens reached a total of 164.1 million viewers, making it the most-viewed show in U.S. history. Figures were tallied from 6:32 p.m. ET until 8:41 p.m. ET and from 9:11 p.m. until 10:47 p.m.

The average number of viewers was put at 108.4 million, which ranked it third.