UPDATE 2pm: The San Francisco 49ers lit up after a 33-minute blackout in the Super Bowl XLVII in New Orleans, but it wasn't enough to stop Baltimore claiming a fairytale 34-31 victory.
The Ravens dominated the first half, and a Super Bowl record 108-yard kickoff return immediately after half-time by Jacoby Jones made the score 28-6.
But 49ers quarterback Colin Kaepernick stepped up after the lights returned, leading the favourites to within one touchdown of a record-breaking comeback.
UPDATE: A power outage has halted play at the Super Bowl in New Orleans.
Electricity was cut to half the Mercedes-Benz Superdome stadium a few minutes into the third quarter.
Power is expected to back up in about 15 minutes. Players have been asked to stay on the field.
At the time of the outage, the Baltimore Ravens were leading 28-6 behind the strong play of their quarterback Joe Flacco.
The third quarter began with Jacoby Jones setting an NFL record with a 109-yard kick return for a touchdown.
EARLIER: The Baltimore Ravens are in the box seat at halftime of Super Bowl XLVII, leading the San Francisco 49ers 21-6.
Ravens quarterback Joe Flacco threw three touchdowns in the opening half, first hooking up with wide receiver Anquan Boldin on the opening drive of the game before finding tight end Dennis Pitta on a short pass in the second quarter.
He then capped off a strong first half with a third touchdown, a 56-yard deep throw to Jacoby Jones.
The 49ers went close to scoring midway through the first quarter with quarterback Colin Kaepernick just overthrowing a pass into the end zone to Michael Crabtree.
San Francisco had to settle for a 36-yard field goal. David Akers kicked a second field goal right at the end of the half.
The Baltimore defense kept Kaepernick at bay in the opening half with the rookie throwing just eight completions for 139 yards, including one interception.
It was the second turnover of the half for the 49ers after LaMichael James fumbled at the start of the second quarter
The Ravens are looking to capture the second ever Super Bowl title after winning their first in 2001.
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