The Ravens turned the miscue into a 20-13 lead. Flacco completed a 19-yard pass to Dennis Pitta before Ray Rice took a handoff, veered right, then broke left and outside for a 34-yard score.
The bickering between these two familiar foes began with the opening kickoff, when several players had to be separated after Baltimore's Jacoby Jones downed the ball for a touchback.
Flacco then threw six straight passes before the Ravens had to punt, and Batch moved the Steelers 48 yards in 11 plays to set up a 46-yard field goal for a 3-0 lead.
Baltimore tied it early in the second quarter when rookie Justin Tucker capped a 40-yard drive with a 45-yard field goal. Then, after Pittsburgh went three-and-out, a pass interference call against Cortez Allen accounted for 30 yards in a 54-yard drive that produced Tucker's second field goal.
Just when it appeared the Ravens were taking control, Flacco threw an up-for-grabs floater that was intercepted by Ryan Clark near midfield. Pittsburgh gave it right back, though, when wide receiver Antonio Brown took a handoff and ran left before throwing a pass across the field that was picked off by Corey Graham.
Baltimore didn't waste the gift. Flacco connected twice with Anquan Boldin during a four-play, 69-yard drive, including a 31-yard touchdown throw just beyond Allen's reach to make it 13-3.
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